diff mbox series

[FFmpeg-devel,RFC,v2] avformat/dashdec: Improve implementation

Message ID 20210410003642.gb6sns4sfzhp427c@localhost
State New
Headers show
Series [FFmpeg-devel,RFC,v2] avformat/dashdec: Improve implementation
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Commit Message

zsugabubus April 10, 2021, 12:37 a.m. UTC
Signed-off-by: zsugabubus <zsugabubus@national.shitposting.agency>
---
Should compile fine now.

 libavformat/dashdec.c  | 4614 +++++++++++++++++++++++++++++++++++++++++++-------------------------------
 libavformat/internal.h |   27 +
 libavformat/utils.c    |   47 +
 3 files changed, 2757 insertions(+), 1931 deletions(-)

Comments

Andreas Rheinhardt April 10, 2021, 12:59 a.m. UTC | #1
zsugabubus:
> Signed-off-by: zsugabubus <zsugabubus@national.shitposting.agency>
> ---
> Should compile fine now.
> 
>  libavformat/dashdec.c  | 4614 +++++++++++++++++++++++++++++++++++++++++++-------------------------------
>  libavformat/internal.h |   27 +
>  libavformat/utils.c    |   47 +
>  3 files changed, 2757 insertions(+), 1931 deletions(-)
> 
>  /**
> @@ -927,6 +941,19 @@ int ff_unlock_avformat(void);
>   */
>  void ff_format_set_url(AVFormatContext *s, char *url);
>  
> +/*
> + * Set parent for subdemuxer opened s context. Also inherit some basic
> + * properties.
> + */
> +void ff_format_set_parent(AVFormatContext *s, AVFormatContext *parent);
> +
> +/**
> + * Get the AVFormatContext that this context originates from. This context
> + * usually the one that was explicitly created by the user so it is useful for
> + * callbacks that would like to refer that specific context.
> + */
> +AVFormatContext *ff_format_get_origin(AVFormatContext *s);
> +

You have added declarations for these two functions, yet not defined them.

>  void avpriv_register_devices(const AVOutputFormat * const o[], const AVInputFormat * const i[]);
>  
>  #endif /* AVFORMAT_INTERNAL_H */
diff mbox series

Patch

diff --git a/libavformat/dashdec.c b/libavformat/dashdec.c
index 6f3f28d..b7a2548 100644
--- a/libavformat/dashdec.c
+++ b/libavformat/dashdec.c
@@ -1,7 +1,8 @@ 
 /*
- * Dynamic Adaptive Streaming over HTTP demux
+ * Dynamic Adaptive Streaming over HTTP demuxer
  * Copyright (c) 2017 samsamsam@o2.pl based on HLS demux
  * Copyright (c) 2017 Steven Liu
+ * Copyright (c) 2020 reworked by zsugabubus
  *
  * This file is part of FFmpeg.
  *
@@ -19,182 +20,401 @@ 
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
+
+/**
+ * @file
+ * Dynamic Adaptive Streaming over HTTP demuxer
+ * @author samsamsam@o2.pl
+ * @author Steven Liu
+ * @author reworked by zsugabubus
+ * @see DASH-IF spec: https://dashif-documents.azurewebsites.net/DASH-IF-IOP/master/DASH-IF-IOP.html
+ * @see another spec: https://dashif-documents.azurewebsites.net/Guidelines-TimingModel/master/Guidelines-TimingModel.html
+ * @see test vectors: https://testassets.dashif.org/
+ * @see MPD scheme: https://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd
+ */
+
 #include <libxml/parser.h>
+#include "libavutil/encryption_info.h"
 #include "libavutil/intreadwrite.h"
+#include "libavutil/lfg.h"
+#include "libavutil/random_seed.h"
+#include "libavutil/avassert.h"
 #include "libavutil/opt.h"
 #include "libavutil/time.h"
 #include "libavutil/parseutils.h"
 #include "internal.h"
 #include "avio_internal.h"
-#include "dash.h"
+#include "libavutil/base64.h"
+
+#if CONFIG_HTTP_PROTOCOL
+# include "http.h"
+#endif
+
+#define MICROSEC_PER_SEC 1000000L
+#define MILLISEC_PER_SEC (MICROSEC_PER_SEC / 1000L)
 
-#define INITIAL_BUFFER_SIZE 32768
-#define MAX_BPRINT_READ_SIZE (UINT_MAX - 1)
-#define DEFAULT_MANIFEST_SIZE 8 * 1024
+static const char CENC_NAMESPACE[] = "urn:mpeg:cenc:2013";
 
-struct fragment {
-    int64_t url_offset;
-    int64_t size;
-    char *url;
+enum {
+    /* Most init section <1K, but some DRM systems can use 600 or so bytes for
+     * PSSH data. */
+    INITBUF_MAX = 4 * 1024
 };
 
-/*
- * reference to : ISO_IEC_23009-1-DASH-2012
- * Section: 5.3.9.6.2
- * Table: Table 17 — Semantics of SegmentTimeline element
- * */
-struct timeline {
-    /* starttime: Element or Attribute Name
-     * specifies the MPD start time, in @timescale units,
-     * the first Segment in the series starts relative to the beginning of the Period.
-     * The value of this attribute must be equal to or greater than the sum of the previous S
-     * element earliest presentation time and the sum of the contiguous Segment durations.
-     * If the value of the attribute is greater than what is expressed by the previous S element,
-     * it expresses discontinuities in the timeline.
-     * If not present then the value shall be assumed to be zero for the first S element
-     * and for the subsequent S elements, the value shall be assumed to be the sum of
-     * the previous S element's earliest presentation time and contiguous duration
-     * (i.e. previous S@starttime + @duration * (@repeat + 1)).
-     * */
-    int64_t starttime;
-    /* repeat: Element or Attribute Name
-     * specifies the repeat count of the number of following contiguous Segments with
-     * the same duration expressed by the value of @duration. This value is zero-based
-     * (e.g. a value of three means four Segments in the contiguous series).
-     * */
-    int64_t repeat;
-    /* duration: Element or Attribute Name
-     * specifies the Segment duration, in units of the value of the @timescale.
-     * */
+#define xml_for_each_attr /* { ... } */ \
+    for (xmlAttrPtr attr = node->properties; \
+         attr; \
+         attr = attr->next) \
+        for (xmlChar *value = xmlNodeGetContent(attr->children); \
+             value; \
+             xml_freep(&value))
+
+#define xml_for_each_child /* { ... } */ \
+    for (xmlNodePtr child = xmlFirstElementChild(node); \
+         child; \
+         child = xmlNextElementSibling(child))
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*x))
+
+#define DASH_RANGE_INITIALIZER (DASHRange){ .start = 0, .end = INT64_MAX }
+
+typedef struct {
+    int64_t start;
+    int64_t end;
+} DASHRange;
+
+typedef struct {
+    xmlChar *url;
+    DASHRange range;
+} DASHSegment;
+
+typedef struct {
+    xmlChar *id;
+    int64_t start_ts;
+    int64_t end_ts;
+    AVDictionary *metadata;
+} DASHPeriod;
+
+typedef struct {
+    int64_t start_ts; /* Relative to timeline. */
+    uint64_t number; /**< $Number$ */
+    int64_t repeat; /**< number..=(number + repeat) */
     int64_t duration;
+} DASHSegmentTemplate;
+
+typedef struct {
+    unsigned refcount;
+    unsigned nb;
+    char *elems[];
+} DASHURLList;
+
+typedef struct {
+    AVIOContext *pb; /**< IO context for reading segment. */
+    uint64_t segment_size; /**< Size of segment to read. */
+} DASHSegmentContext;
+
+typedef struct {
+    xmlChar *id;
+
+    unsigned refcount;
+    AVDictionary *metadata;
+    AVEncryptionInitInfo *init_info; /**< Chain of initialization infos
+                                       extracted from the manifest. */
+} DASHAdaptationSet;
+
+enum DASHTimelineType {
+    TIMELINE_TEMPLATES, /**< DASHTimeline.u.templates */
+    TIMELINE_SEGMENTS, /**< DASHTimeline.u.segments */
 };
 
-/*
- * Each playlist has its own demuxer. If it is currently active,
- * it has an opened AVIOContext too, and potentially an AVPacket
- * containing the next packet from this stream.
- */
-struct representation {
-    char *url_template;
-    AVIOContext pb;
-    AVIOContext *input;
-    AVFormatContext *parent;
-    AVFormatContext *ctx;
-    int stream_index;
-
-    char *id;
-    char *lang;
-    int bandwidth;
-    AVRational framerate;
-    AVStream *assoc_stream; /* demuxer stream associated with this representation */
-
-    int n_fragments;
-    struct fragment **fragments; /* VOD list of fragment for profile */
-
-    int n_timelines;
-    struct timeline **timelines;
-
-    int64_t first_seq_no;
-    int64_t last_seq_no;
-    int64_t start_number; /* used in case when we have dynamic list of segment to know which segments are new one*/
-
-    int64_t fragment_duration;
-    int64_t fragment_timescale;
-
-    int64_t presentation_timeoffset;
-
-    int64_t cur_seq_no;
-    int64_t cur_seg_offset;
-    int64_t cur_seg_size;
-    struct fragment *cur_seg;
-
-    /* Currently active Media Initialization Section */
-    struct fragment *init_section;
-    uint8_t *init_sec_buf;
-    uint32_t init_sec_buf_size;
-    uint32_t init_sec_data_len;
-    uint32_t init_sec_buf_read_offset;
-    int64_t cur_timestamp;
-    int is_restart_needed;
+typedef struct {
+    unsigned refcount;
+    enum DASHTimelineType type;
+    int64_t duration;
+    int64_t timescale;
+    DASHSegment init;
+    union {
+        struct {
+            unsigned nb;
+            DASHSegment elems[];
+        } segments;
+        struct {
+            unsigned nb;
+            DASHSegment master;
+            DASHSegmentTemplate elems[];
+        } templates;
+    } u;
+} DASHTimeline;
+
+#define DASH_PARAMETERS_INITIALIZER { \
+    .sample_aspect_ratio = { 0, 1 }, \
+    .field_order = AV_FIELD_PROGRESSIVE, \
+}
+
+typedef struct {
+    enum AVMediaType codec_type;
+    enum AVCodecID codec_id;
+    int profile;
+    int level;
+    int disposition;
+
+    /* Audio only. */
+    int sample_rate;
+    int channels;
+    uint64_t channel_layout;
+    enum AVMatrixEncoding matrix_encoding;
+
+    /* Video only. */
+    int width;
+    int height;
+    AVRational frame_rate;
+    AVRational sample_aspect_ratio;
+    enum AVFieldOrder field_order;
+} DASHParameters;
+
+typedef struct {
+    DASHPeriod *period;
+    DASHAdaptationSet *as;
+    DASHTimeline *timeline;
+    DASHURLList *base;
+    uint32_t bandwidth;
+
+    char *initbuf;
+    int initbuf_size; /* Limited by INITBUF_MAX. */
+
+    DASHParameters par;
+} DASHRepresentationPeriod;
+
+typedef struct {
+    xmlChar *id;
+
+    AVFormatContext *oc; /* := DASHContext.ctx */
+    AVStream **ostreams; /**< Corresponding output streams. */
+    AVFormatContext *ic;
+    unsigned nb_streams; /**< Should be := ic->nb_streams. If less, subdemuxer
+                           created new streams. */
+
+    AVIOContext ic_pb; /**< Custom IO context for ic subdemuxer. */
+
+    int save_init; /**< Whether to store what we have read from the current segment. */
+    DASHRepresentationPeriod **periods;
+    unsigned nb_periods;
+    DASHRepresentationPeriod *cur_period;
+
+    int64_t last_pts;
+    int64_t read_ts;
+
+    unsigned cur_segment;
+    DASHSegmentContext segments[];
+} DASHRepresentation;
+
+enum DASHUTCTiming {
+    DASH_UTC_TIMING_LOCAL,
+    DASH_UTC_TIMING_HTTP_XSDATE,
+    DASH_UTC_TIMING_HTTP_ISO,
+    DASH_UTC_TIMING_HTTP_NTP,
+    DASH_UTC_TIMING_NTP,
+    DASH_UTC_TIMING_HTTP_HEAD,
+    DASH_UTC_TIMING_DIRECT,
 };
 
-typedef struct DASHContext {
+typedef struct {
     const AVClass *class;
-    char *base_url;
 
-    int n_videos;
-    struct representation **videos;
-    int n_audios;
-    struct representation **audios;
-    int n_subtitles;
-    struct representation **subtitles;
-
-    /* MediaPresentationDescription Attribute */
-    uint64_t media_presentation_duration;
-    uint64_t suggested_presentation_delay;
-    uint64_t availability_start_time;
-    uint64_t availability_end_time;
-    uint64_t publish_time;
-    uint64_t minimum_update_period;
-    uint64_t time_shift_buffer_depth;
-    uint64_t min_buffer_time;
-
-    /* Period Attribute */
-    uint64_t period_duration;
-    uint64_t period_start;
-
-    /* AdaptationSet Attribute */
-    char *adaptionset_lang;
-
-    int is_live;
-    AVIOInterruptCB *interrupt_callback;
-    char *allowed_extensions;
-    AVDictionary *avio_opts;
-    int max_url_size;
-
-    /* Flags for init section*/
-    int is_init_section_common_video;
-    int is_init_section_common_audio;
-    int is_init_section_common_subtitle;
+    xmlChar *id;
+
+    char *location;
+    xmlChar *chain_next_location;
+    xmlChar *fallback_location;
+
+    unsigned nb_connections;
 
+    DASHPeriod **periods;
+    unsigned nb_periods;
+
+    DASHAdaptationSet **ass;
+    unsigned nb_ass;
+
+    DASHRepresentation **reps;
+    unsigned nb_reps;
+
+    int is_live; /**< Segments may get available over time. */
+    int64_t start_ts;
+
+    int64_t media_presentation_duration;
+    int64_t suggested_presentation_delay;
+    int64_t availability_start_time;
+    int64_t availability_end_time;
+    int64_t publish_time;
+    int64_t min_update_period;
+    int64_t time_shift_buffer_depth;
+    int64_t min_buffer_time;
+    int64_t max_segment_duration;
+
+    int64_t next_update;
+
+    int64_t time_diff;
+    int utc_timing; /* DASH_UTC_TIMING_*; < 0 if updated */
+
+    AVLFG rnd;
+
+    AVDictionary *protocol_opts;
 } DASHContext;
 
-static int ishttp(char *url)
+typedef struct {
+    xmlChar *scheme_id;
+    xmlChar *value;
+    xmlAttrPtr scheme_id_attr;
+} DASHScheme;
+
+#define DASH_CONTENTPROTECTION_INITIALIZER { .has_key_id = 0 }
+
+typedef struct {
+    int has_key_id;
+    uint8_t default_kid[16];
+} DASHContentProtection;
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstrict-prototypes"
+static av_cold void av_freep_arrayp(void *ptr, void (*free)())
+{
+    unsigned *nmemb = (unsigned *)((void **)ptr + 1);
+
+    for (unsigned i = 0; i < *nmemb; ++i)
+        ((void(*)(void *))free)((*(void ***)ptr)[i]);
+
+    *nmemb = 0;
+    av_freep(ptr);
+}
+#pragma GCC diagnostic pop
+
+static void xml_free(xmlChar *p)
+{
+    if (p)
+        xmlFree(p);
+}
+
+static void xml_freep(xmlChar **pp)
+{
+    if (*pp) {
+        xmlFree(*pp);
+        *pp = NULL;
+    }
+}
+
+static av_cold DASHURLList *dash_ref_urllist(DASHURLList *urls)
+{
+    ++urls->refcount;
+    return urls;
+}
+
+static av_cold void dash_unref_urllist(DASHURLList *urls)
+{
+    if (!urls || --urls->refcount)
+        return;
+
+    for (unsigned i = 0; i < urls->nb; ++i)
+        av_free(urls->elems[i]);
+    av_free(urls);
+}
+
+static int dash_urllist_has(const DASHURLList *urls, const char *url)
+{
+    for (unsigned i = 0; i < urls->nb; ++i)
+        if (!strcmp(urls->elems[i], url))
+            return 1;
+
+    return 0;
+}
+
+static av_cold void dash_free_period(DASHPeriod *period)
+{
+    if (!period)
+        return;
+
+    xml_free(period->id);
+    av_dict_free(&period->metadata);
+    av_free(period);
+}
+
+static av_cold void dash_free_adaptationset(DASHAdaptationSet *as)
+{
+    if (!as)
+        return;
+
+    xml_free(as->id);
+    av_encryption_init_info_free(as->init_info);
+    av_dict_free(&as->metadata);
+    av_free(as);
+}
+
+static av_cold DASHTimeline *dash_ref_timeline(DASHTimeline *timeline)
+{
+    ++timeline->refcount;
+    return timeline;
+}
+
+static void dash_free_segment(DASHSegment *g)
+{
+    xml_free(g->url);
+}
+
+static void dash_unref_timeline(DASHTimeline *timeline)
 {
-    const char *proto_name = avio_find_protocol_name(url);
-    return proto_name && av_strstart(proto_name, "http", NULL);
+    if (!timeline || --timeline->refcount)
+        return;
+
+    dash_free_segment(&timeline->init);
+
+    if (TIMELINE_SEGMENTS == timeline->type) {
+        for (unsigned i = 0; i < timeline->u.segments.nb; ++i)
+            dash_free_segment(&timeline->u.segments.elems[i]);
+    } else if (TIMELINE_TEMPLATES == timeline->type) {
+        dash_free_segment(&timeline->u.templates.master);
+    } else {
+        abort();
+    }
+
+    av_free(timeline);
 }
 
-static int aligned(int val)
+/**
+ * @return |wall_time| / MICROSEC_PER_SEC * AV_TIME_BASE
+ */
+static int64_t av_wall2timebase(int64_t wall_time)
 {
-    return ((val + 0x3F) >> 6) << 6;
+    if (MICROSEC_PER_SEC < AV_TIME_BASE)
+        return wall_time * (AV_TIME_BASE / MICROSEC_PER_SEC);
+    else
+        return wall_time / (MICROSEC_PER_SEC / AV_TIME_BASE);
 }
 
-static uint64_t get_current_time_in_sec(void)
+/**
+ * @return wall clock time in AV_TIME_BASE
+ */
+static int64_t dash_gettime(AVFormatContext *s)
 {
-    return  av_gettime() / 1000000;
+    DASHContext *c = s->priv_data;
+    return av_wall2timebase(av_gettime()) + c->time_diff;
 }
 
-static uint64_t get_utc_date_time_insec(AVFormatContext *s, const char *datetime)
+/**
+ * Parse ISO-8601 date.
+ * @return time in AV_TIME_BASE
+ */
+static uint64_t dash_parse_date(const char *s, AVFormatContext *log_ctx)
 {
     struct tm timeinfo;
-    int year = 0;
-    int month = 0;
-    int day = 0;
-    int hour = 0;
-    int minute = 0;
-    int ret = 0;
+    unsigned year = 0, month = 0, day = 0;
+    unsigned hour = 0, minute = 0;
     float second = 0.0;
 
-    /* ISO-8601 date parser */
-    if (!datetime)
-        return 0;
+    if (6 != av_sscanf(s, "%u-%u-%uT%u:%u:%fZ",
+                       &year, &month, &day,
+                       &hour, &minute, &second))
+        av_log(log_ctx, AV_LOG_WARNING, "Malformed ISO-8601 date: '%s'\n", s);
+        /* Fall-through. */
 
-    ret = sscanf(datetime, "%d-%d-%dT%d:%d:%fZ", &year, &month, &day, &hour, &minute, &second);
-    /* year, month, day, hour, minute, second  6 arguments */
-    if (ret != 6) {
-        av_log(s, AV_LOG_WARNING, "get_utc_date_time_insec get a wrong time format\n");
-    }
     timeinfo.tm_year = year - 1900;
     timeinfo.tm_mon  = month - 1;
     timeinfo.tm_mday = day;
@@ -205,2189 +425,2719 @@  static uint64_t get_utc_date_time_insec(AVFormatContext *s, const char *datetime
     return av_timegm(&timeinfo);
 }
 
-static uint32_t get_duration_insec(AVFormatContext *s, const char *duration)
+/**
+ * Parse ISO-8601 duration.
+ * @return duration in AV_TIME_BASE
+ */
+static int64_t dash_parse_duration(const char *s, AVFormatContext *log_ctx)
 {
-    /* ISO-8601 duration parser */
-    uint32_t days = 0;
-    uint32_t hours = 0;
-    uint32_t mins = 0;
-    uint32_t secs = 0;
-    int size = 0;
-    float value = 0;
-    char type = '\0';
-    const char *ptr = duration;
-
-    while (*ptr) {
-        if (*ptr == 'P' || *ptr == 'T') {
-            ptr++;
+    enum {
+        STATE_GROUND,
+        STATE_DATE,
+        STATE_TIME,
+    } state = STATE_GROUND;
+    int64_t ret = 0;
+
+    for (const char *p = s; *p; ++p) {
+        int len;
+        int64_t unit = 0;
+        /* We require double precision since it is absolutely valid to pass a
+         * huge integer solely in seconds. */
+        double base;
+
+        switch (*p) {
+        case 'P':
+            if (state != STATE_GROUND)
+                goto invalid;
+            state = STATE_DATE;
+            continue;
+        case 'T':
+            if (state != STATE_DATE)
+                goto invalid;
+            state = STATE_TIME;
             continue;
         }
 
-        if (sscanf(ptr, "%f%c%n", &value, &type, &size) != 2) {
-            av_log(s, AV_LOG_WARNING, "get_duration_insec get a wrong time format\n");
-            return 0; /* parser error */
-        }
-        switch (type) {
-        case 'D':
-            days = (uint32_t)value;
-            break;
-        case 'H':
-            hours = (uint32_t)value;
-            break;
-        case 'M':
-            mins = (uint32_t)value;
-            break;
-        case 'S':
-            secs = (uint32_t)value;
+        av_sscanf(p, "%lf%n", &base, &len);
+        p += len;
+
+        switch (state) {
+        case STATE_DATE:
+            switch (*p) {
+            case 'Y':
+                unit = (int64_t)AV_TIME_BASE * 60 * 60 * 24 * 365;
+                break;
+            case 'M':
+                unit = (int64_t)AV_TIME_BASE * 60 * 60 * 24 * 30;
+                break;
+            case 'D':
+                unit = (int64_t)AV_TIME_BASE * 60 * 60 * 24;
+                break;
+            }
             break;
-        default:
-            // handle invalid type
+        case STATE_TIME:
+            switch (*p) {
+            case 'H':
+                unit = (int64_t)AV_TIME_BASE * 60 * 60;
+                break;
+            case 'M':
+                unit = (int64_t)AV_TIME_BASE * 60;
+                break;
+            case 'S':
+                unit = (int64_t)AV_TIME_BASE;
+                break;
+            }
             break;
         }
-        ptr += size;
+
+        if (!unit) {
+        invalid:
+            av_log(log_ctx, AV_LOG_ERROR, "Malformed ISO-8601 duration: '%s'\n", s);
+            return INT64_MIN;
+        }
+
+        ret += unit * base;
     }
-    return  ((days * 24 + hours) * 60 + mins) * 60 + secs;
+
+    return ret;
 }
 
-static int64_t get_segment_start_time_based_on_timeline(struct representation *pls, int64_t cur_seq_no)
+static av_cold void dash_subdemuxer_flush(DASHRepresentation *rep)
 {
-    int64_t start_time = 0;
-    int64_t i = 0;
-    int64_t j = 0;
-    int64_t num = 0;
+    DASHContext *c = rep->oc->priv_data;
 
-    if (pls->n_timelines) {
-        for (i = 0; i < pls->n_timelines; i++) {
-            if (pls->timelines[i]->starttime > 0) {
-                start_time = pls->timelines[i]->starttime;
-            }
-            if (num == cur_seq_no)
-                goto finish;
+    avio_flush(&rep->ic_pb);
+    for (unsigned i = 0; i < c->nb_connections; ++i)
+        ff_format_io_close(rep->oc, &rep->segments[i].pb);
 
-            start_time += pls->timelines[i]->duration;
 
-            if (pls->timelines[i]->repeat == -1) {
-                start_time = pls->timelines[i]->duration * cur_seq_no;
-                goto finish;
-            }
+    /* for (unsigned i = 0; i < rep->nb_streams; ++i)
+            avcodec_flush_buffers(rep->ostreams[i]->internal->avctx); */
 
-            for (j = 0; j < pls->timelines[i]->repeat; j++) {
-                num++;
-                if (num == cur_seq_no)
-                    goto finish;
-                start_time += pls->timelines[i]->duration;
-            }
-            num++;
+    if (rep->ic) {
+        /* for (unsigned i = 0; i < rep->ic->nb_streams; ++i)
+                avcodec_flush_buffers(rep->ic->streams[i]->internal->avctx); */
+        avformat_flush(rep->ic);
+    }
+
+    /* If receiving init section just has been aborted, we have to forget all
+     * received bytes otherwise at subdemuxer restart on the first read it will
+     * be falsely detected that we have received the complete section because
+     * stored init section size is less than maximum storable. */
+    if (rep->save_init) {
+        rep->save_init = 0;
+        if (rep->cur_period) {
+            rep->cur_period->initbuf_size = 0;
+            rep->cur_period = NULL;
         }
     }
-finish:
-    return start_time;
 }
 
-static int64_t calc_next_seg_no_from_timelines(struct representation *pls, int64_t cur_time)
+static av_cold void dash_subdemuxer_close(DASHRepresentation *rep)
 {
-    int64_t i = 0;
-    int64_t j = 0;
-    int64_t num = 0;
-    int64_t start_time = 0;
+    av_log(rep->oc, AV_LOG_DEBUG, "Closing representation '%s'\n", rep->id);
 
-    for (i = 0; i < pls->n_timelines; i++) {
-        if (pls->timelines[i]->starttime > 0) {
-            start_time = pls->timelines[i]->starttime;
-        }
-        if (start_time > cur_time)
-            goto finish;
-
-        start_time += pls->timelines[i]->duration;
-        for (j = 0; j < pls->timelines[i]->repeat; j++) {
-            num++;
-            if (start_time > cur_time)
-                goto finish;
-            start_time += pls->timelines[i]->duration;
+    /* Only need to deallocate the used array. */
+    av_freep(&rep->ic_pb.buffer);
+
+    dash_subdemuxer_flush(rep);
+
+    if (rep->ic) {
+        /* IO context is part of our context so avoid freeing it. */
+        rep->ic->pb = NULL;
+        rep->cur_period = NULL;
+
+        if (rep->ic->iformat) {
+            avformat_close_input(&rep->ic);
+        } else {
+            avformat_free_context(rep->ic);
+            rep->ic = NULL;
         }
-        num++;
     }
+}
 
-    return -1;
+static av_cold void dash_free_representationperiod(DASHRepresentationPeriod *period)
+{
+    dash_unref_timeline(period->timeline);
+    dash_unref_urllist(period->base);
+    av_free(period->initbuf);
+    av_free(period);
+}
 
-finish:
-    return num;
+static av_cold void dash_free_representation(DASHRepresentation *rep)
+{
+    dash_subdemuxer_close(rep);
+    av_free(rep->ostreams);
+    av_freep_arrayp(&rep->periods, dash_free_representationperiod);
+    xml_free(rep->id);
+    av_free(rep);
 }
 
-static void free_fragment(struct fragment **seg)
+static av_cold xmlNodePtr xml_get_nsnode(xmlNodePtr node, const char *nodename, const char *namespace)
 {
-    if (!(*seg)) {
-        return;
-    }
-    av_freep(&(*seg)->url);
-    av_freep(seg);
+    xml_for_each_child
+        if (!strcmp(child->name, nodename) &&
+            (child->ns && !strcmp(child->ns->href, namespace)))
+            return child;
+    return NULL;
 }
 
-static void free_fragment_list(struct representation *pls)
+static av_cold int dash_parse_contentprotection_pssh(AVFormatContext *s,
+                                                     struct AVEncryptionInitInfo *info,
+                                                     xmlNodePtr node)
 {
-    int i;
+    int ret = 0;
+    xmlNodePtr pssh_node;
+    int size;
+    char *pssh = NULL;
+    int decoded_size;
+    uint8_t *decoded_pssh;
+
+    av_free(info->data);
+    info->data = NULL;
+    info->data_size = 0;
 
-    for (i = 0; i < pls->n_fragments; i++) {
-        free_fragment(&pls->fragments[i]);
+    if (!(pssh_node = xml_get_nsnode(node, "pssh", CENC_NAMESPACE)))
+        goto out;
+
+    if (!(pssh = xmlNodeGetContent(pssh_node)))
+        goto invalid_content;
+
+    size = strlen(pssh);
+    decoded_size = AV_BASE64_DECODE_SIZE(size);
+
+    if (!(decoded_pssh = av_malloc(decoded_size))) {
+        ret = AVERROR(ENOMEM);
+        goto out;
     }
-    av_freep(&pls->fragments);
-    pls->n_fragments = 0;
-}
 
-static void free_timelines_list(struct representation *pls)
-{
-    int i;
+    if ((decoded_size = av_base64_decode(decoded_pssh, pssh, decoded_size)) < 0) {
+        av_free(decoded_pssh);
 
-    for (i = 0; i < pls->n_timelines; i++) {
-        av_freep(&pls->timelines[i]);
+    invalid_content:
+        av_log(s, AV_LOG_ERROR, "Invalid %s/{%s}:pssh content\n",
+               node->name, CENC_NAMESPACE);
+        ret = AVERROR_INVALIDDATA;
+        goto out;
     }
-    av_freep(&pls->timelines);
-    pls->n_timelines = 0;
+
+    info->data = decoded_pssh;
+    info->data_size = decoded_size;
+
+out:
+    xml_free(pssh);
+    return ret;
 }
 
-static void free_representation(struct representation *pls)
+static av_cold void dash_free_scheme(DASHScheme *scheme)
 {
-    free_fragment_list(pls);
-    free_timelines_list(pls);
-    free_fragment(&pls->cur_seg);
-    free_fragment(&pls->init_section);
-    av_freep(&pls->init_sec_buf);
-    av_freep(&pls->pb.buffer);
-    ff_format_io_close(pls->parent, &pls->input);
-    if (pls->ctx) {
-        pls->ctx->pb = NULL;
-        avformat_close_input(&pls->ctx);
-    }
+    xml_free(scheme->scheme_id);
+    xml_free(scheme->value);
+}
 
-    av_freep(&pls->url_template);
-    av_freep(&pls->lang);
-    av_freep(&pls->id);
-    av_freep(&pls);
+static av_cold void dash_log_invalid_attr_value(AVFormatContext *log_ctx, xmlAttrPtr attr, const char *value)
+{
+    av_log(log_ctx, AV_LOG_ERROR, "Invalid %s/%s@%s%s%s%s='%s'\n",
+           attr->parent->parent->name,
+           attr->parent->ns ? "{" : "",
+           attr->parent->ns ? (const char *)attr->parent->ns->href : "",
+           attr->parent->ns ? "}" : "",
+           attr->parent->name,
+           attr->name,
+           value);
 }
 
-static void free_video_list(DASHContext *c)
+static av_cold void dash_log_missing_attr(AVFormatContext *log_ctx, xmlNodePtr node, const char *attr)
 {
-    int i;
-    for (i = 0; i < c->n_videos; i++) {
-        struct representation *pls = c->videos[i];
-        free_representation(pls);
-    }
-    av_freep(&c->videos);
-    c->n_videos = 0;
+    av_log(log_ctx, AV_LOG_ERROR, "Missing %s/%s@%s\n",
+           node->parent->name,
+           node->name,
+           attr);
 }
 
-static void free_audio_list(DASHContext *c)
+static av_cold void dash_log_unknown_child(AVFormatContext *log_ctx, xmlNodePtr child)
 {
-    int i;
-    for (i = 0; i < c->n_audios; i++) {
-        struct representation *pls = c->audios[i];
-        free_representation(pls);
-    }
-    av_freep(&c->audios);
-    c->n_audios = 0;
+    av_log(log_ctx, AV_LOG_WARNING, "Unknown %s/%s\n",
+           child->parent->name,
+           child->name);
 }
 
-static void free_subtitle_list(DASHContext *c)
+static av_cold void dash_log_unknown_attr(AVFormatContext *log_ctx, xmlAttrPtr attr, const xmlChar *value)
 {
-    int i;
-    for (i = 0; i < c->n_subtitles; i++) {
-        struct representation *pls = c->subtitles[i];
-        free_representation(pls);
-    }
-    av_freep(&c->subtitles);
-    c->n_subtitles = 0;
+    av_log(log_ctx, AV_LOG_WARNING, "Unknown %s%s%s@%s%s%s%s='%s'\n",
+           attr->parent->parent->name ? (const char *)attr->parent->parent->name : "",
+           attr->parent->parent->name ? "/"                                      : "",
+           attr->parent->name,
+           attr->ns ? "{" : "",
+           attr->ns ? (const char *)attr->ns->href : "",
+           attr->ns ? "}:" : "",
+           attr->name,
+           value);
 }
 
-static int open_url(AVFormatContext *s, AVIOContext **pb, const char *url,
-                    AVDictionary **opts, AVDictionary *opts2, int *is_http)
+static av_cold void dash_log_unknown_scheme(AVFormatContext *log_ctx, const DASHScheme *scheme)
 {
-    DASHContext *c = s->priv_data;
-    AVDictionary *tmp = NULL;
-    const char *proto_name = NULL;
-    int ret;
+    av_log(log_ctx, AV_LOG_WARNING,
+           "Unknown %s/%s@%s='%s' (@value=%c%s%c)\n",
+           scheme->scheme_id_attr->parent->parent->name,
+           scheme->scheme_id_attr->parent->name,
+           scheme->scheme_id_attr->name,
+           scheme->scheme_id,
+           scheme->value ? '\''                        : '(',
+           scheme->value ? (const char *)scheme->value : "not present",
+           scheme->value ? '\''                        : ')');
+}
+
+static av_cold int dash_parse_scheme(AVFormatContext *s, DASHScheme *scheme, int value_required, xmlNodePtr node)
+{
+    scheme->value = NULL;
 
-    if (av_strstart(url, "crypto", NULL)) {
-        if (url[6] == '+' || url[6] == ':')
-            proto_name = avio_find_protocol_name(url + 7);
+    if (!(scheme->scheme_id_attr = xmlHasNsProp(node, "schemeIdUri", NULL))) {
+        dash_log_missing_attr(s, node, "schemeIdUri");
+        return AVERROR_INVALIDDATA;
     }
 
-    if (!proto_name)
-        proto_name = avio_find_protocol_name(url);
+    if (!(scheme->scheme_id = xmlNodeGetContent(scheme->scheme_id_attr->children)))
+        return AVERROR(ENOMEM);
 
-    if (!proto_name)
+    if (!(scheme->value = xmlGetNoNsProp(node, "value")) && value_required) {
+        dash_log_missing_attr(s, node, "value");
         return AVERROR_INVALIDDATA;
+    }
 
-    // only http(s) & file are allowed
-    if (av_strstart(proto_name, "file", NULL)) {
-        if (strcmp(c->allowed_extensions, "ALL") && !av_match_ext(url, c->allowed_extensions)) {
-            av_log(s, AV_LOG_ERROR,
-                   "Filename extension of \'%s\' is not a common multimedia extension, blocked for security reasons.\n"
-                   "If you wish to override this adjust allowed_extensions, you can set it to \'ALL\' to allow all\n",
-                   url);
-            return AVERROR_INVALIDDATA;
-        }
-    } else if (av_strstart(proto_name, "http", NULL)) {
-        ;
-    } else
-        return AVERROR_INVALIDDATA;
+    return 0;
+}
 
-    if (!strncmp(proto_name, url, strlen(proto_name)) && url[strlen(proto_name)] == ':')
-        ;
-    else if (av_strstart(url, "crypto", NULL) && !strncmp(proto_name, url + 7, strlen(proto_name)) && url[7 + strlen(proto_name)] == ':')
-        ;
-    else if (strcmp(proto_name, "file") || !strncmp(url, "file,", 5))
-        return AVERROR_INVALIDDATA;
+static av_cold int dash_parse_contentprotection(AVFormatContext *s,
+                                                DASHAdaptationSet *as,
+                                                DASHContentProtection *cp,
+                                                xmlNodePtr node)
+{
+    int ret = 0;
+    AVEncryptionInitInfo *init_info = NULL;
+    const char *uuid;
+    DASHScheme scheme;
+
+    if ((ret = dash_parse_scheme(s, &scheme, 0, node)) < 0)
+        goto out;
+
+    /* Parse Common Encryption element. */
+    if (!cp->has_key_id &&
+        !strcmp(scheme.scheme_id, "urn:mpeg:dash:mp4protection:2011") &&
+        (scheme.value && !strcmp(scheme.value, "cenc")))
+    {
+        char *key_id;
+
+        if ((key_id = xmlGetNsProp(node, "default_KID", CENC_NAMESPACE))) {
+            if (ff_uuid_to_data(cp->default_kid, key_id) < 0)
+                av_log(s, AV_LOG_ERROR, "Malformed UUID in ContentProtection@cenc:default_KID='%s'\n",
+                       scheme.scheme_id);
+            else
+                cp->has_key_id = 1;
 
-    av_freep(pb);
-    av_dict_copy(&tmp, *opts, 0);
-    av_dict_copy(&tmp, opts2, 0);
-    ret = avio_open2(pb, url, AVIO_FLAG_READ, c->interrupt_callback, &tmp);
-    if (ret >= 0) {
-        // update cookies on http response with setcookies.
-        char *new_cookies = NULL;
+            xmlFree(key_id);
+        } else {
+            dash_log_missing_attr(s, node, "default_KID");
+        }
 
-        if (!(s->flags & AVFMT_FLAG_CUSTOM_IO))
-            av_opt_get(*pb, "cookies", AV_OPT_SEARCH_CHILDREN, (uint8_t**)&new_cookies);
+        goto out;
+    } else if (cp->has_key_id && av_strstart(scheme.scheme_id, "urn:uuid:", &uuid)) {
+        /* Parse an UUID schema. */
+        init_info = av_encryption_init_info_alloc(/* system_id_size */ 16, 1,
+                                                  /* key_id_size */ 16, /* data_size */ 0);
+        if (!init_info) {
+            ret = AVERROR(ENOMEM);
+            goto out;
+        }
 
-        if (new_cookies) {
-            av_dict_set(opts, "cookies", new_cookies, AV_DICT_DONT_STRDUP_VAL);
+        if (ff_uuid_to_data(init_info->system_id, uuid) < 0) {
+            av_log(s, AV_LOG_ERROR, "Malformed UUID in ContentProtection@schemeIdUri='%s'\n",
+                   scheme.scheme_id);
+            goto out;
         }
 
-    }
+        if (0 <= ret)
+            ret = dash_parse_contentprotection_pssh(s, init_info, node);
+        if (ret < 0)
+            goto out;
 
-    av_dict_free(&tmp);
+        memcpy(init_info->key_ids[0], cp->default_kid, init_info->key_id_size);
+
+        init_info->next = as->init_info;
+        as->init_info = init_info;
+        init_info = NULL;
+    } else {
+        dash_log_unknown_scheme(s, &scheme);
+        goto out;
+    }
 
-    if (is_http)
-        *is_http = av_strstart(proto_name, "http", NULL);
+out:
+    if (init_info)
+        av_encryption_init_info_free(init_info);
+    dash_free_scheme(&scheme);
 
     return ret;
 }
 
-static char *get_content_url(xmlNodePtr *baseurl_nodes,
-                             int n_baseurl_nodes,
-                             int max_url_size,
-                             char *rep_id_val,
-                             char *rep_bandwidth_val,
-                             char *val)
+static av_cold int dash_set_location(AVFormatContext *s, char const *url)
 {
-    int i;
-    char *text;
-    char *url = NULL;
-    char *tmp_str = av_mallocz(max_url_size);
-
-    if (!tmp_str)
-        return NULL;
+    DASHContext *c = s->priv_data;
+    URLComponents uc;
+    char const *protocol;
 
-    for (i = 0; i < n_baseurl_nodes; ++i) {
-        if (baseurl_nodes[i] &&
-            baseurl_nodes[i]->children &&
-            baseurl_nodes[i]->children->type == XML_TEXT_NODE) {
-            text = xmlNodeGetContent(baseurl_nodes[i]->children);
-            if (text) {
-                memset(tmp_str, 0, max_url_size);
-                ff_make_absolute_url(tmp_str, max_url_size, "", text);
-                xmlFree(text);
-            }
-        }
-    }
+    if (ff_url_decompose(&uc, url, NULL) < 0)
+        return AVERROR_INVALIDDATA;
 
-    if (val)
-        ff_make_absolute_url(tmp_str, max_url_size, tmp_str, val);
+    av_free(c->location);
+    if (!(c->location = av_strdup(url)))
+        return AVERROR(ENOMEM);
 
-    if (rep_id_val) {
-        url = av_strireplace(tmp_str, "$RepresentationID$", rep_id_val);
-        if (!url) {
-            goto end;
-        }
-        av_strlcpy(tmp_str, url, max_url_size);
-    }
-    if (rep_bandwidth_val && tmp_str[0] != '\0') {
-        // free any previously assigned url before reassigning
-        av_free(url);
-        url = av_strireplace(tmp_str, "$Bandwidth$", rep_bandwidth_val);
-        if (!url) {
-            goto end;
+    protocol = avio_find_protocol_name(c->location);
+    if (strstr(protocol, "http")) {
+        char *p = strstr(uc.query, "t=");
+        if (p) {
+            int64_t seconds;
+
+            p += 2;
+            if (1 == av_sscanf(p, "posix:%"SCNd64, &seconds))
+                c->start_ts = AV_TIME_BASE * seconds;
+            else if (!strncmp(p, "now", 4))
+                c->start_ts = dash_gettime(s);
+            else
+                c->start_ts = dash_parse_date(p, s);
         }
     }
-end:
-    av_free(tmp_str);
-    return url;
+
+    return 0;
 }
 
-static char *get_val_from_nodes_tab(xmlNodePtr *nodes, const int n_nodes, const char *attrname)
+static av_cold int dash_parse_location(AVFormatContext *s,
+                                       xmlNodePtr node)
 {
-    int i;
-    char *val;
+    int ret = 0;
+    char *value;
+    DASHContext *c = s->priv_data;
 
-    for (i = 0; i < n_nodes; ++i) {
-        if (nodes[i]) {
-            val = xmlGetProp(nodes[i], attrname);
-            if (val)
-                return val;
-        }
+    if (!c->is_live) {
+        av_log(s, AV_LOG_INFO, "MPD@type=\"static\"/Location ignored\n");
+        return 0;
     }
 
-    return NULL;
-}
+    if (!(value = xmlNodeGetContent(node)))
+        return AVERROR(ENOMEM);
 
-static xmlNodePtr find_child_node_by_name(xmlNodePtr rootnode, const char *nodename)
-{
-    xmlNodePtr node = rootnode;
-    if (!node) {
-        return NULL;
-    }
+    ret = dash_set_location(s, value);
 
-    node = xmlFirstElementChild(node);
-    while (node) {
-        if (!av_strcasecmp(node->name, nodename)) {
-            return node;
-        }
-        node = xmlNextElementSibling(node);
-    }
-    return NULL;
+    xmlFree(value);
+    return ret;
 }
 
-static enum AVMediaType get_content_type(xmlNodePtr node)
-{
-    enum AVMediaType type = AVMEDIA_TYPE_UNKNOWN;
-    int i = 0;
-    const char *attr;
-    char *val = NULL;
-
-    if (node) {
-        for (i = 0; i < 2; i++) {
-            attr = i ? "mimeType" : "contentType";
-            val = xmlGetProp(node, attr);
-            if (val) {
-                if (av_stristr(val, "video")) {
-                    type = AVMEDIA_TYPE_VIDEO;
-                } else if (av_stristr(val, "audio")) {
-                    type = AVMEDIA_TYPE_AUDIO;
-                } else if (av_stristr(val, "text")) {
-                    type = AVMEDIA_TYPE_SUBTITLE;
-                }
-                xmlFree(val);
-            }
-        }
-    }
-    return type;
+/**
+ * Like ff_make_absolute_urla() but allocates a big enough memory.
+ * *out_url shall always be av_free()d regard of error.
+ * */
+static int ff_make_absolute_urla(char **out_url, const char *base, const char *rel)
+{
+    int out_url_max_size = strlen(base) + strlen(rel) + 1/* NUL */;
+    if (!(*out_url = av_malloc(out_url_max_size)))
+        return AVERROR(ENOMEM);
+
+    return ff_make_absolute_url(*out_url, out_url_max_size, base, rel);
 }
 
-static struct fragment * get_Fragment(char *range)
+static av_cold DASHURLList *dash_new_urllist(unsigned nb_urls)
 {
-    struct fragment * seg =  av_mallocz(sizeof(struct fragment));
+    DASHURLList *urls;
 
-    if (!seg)
+    if (!(urls = av_mallocz(offsetof(DASHURLList, elems[nb_urls]))))
         return NULL;
 
-    seg->size = -1;
-    if (range) {
-        char *str_end_offset;
-        char *str_offset = av_strtok(range, "-", &str_end_offset);
-        seg->url_offset = strtoll(str_offset, NULL, 10);
-        seg->size = strtoll(str_end_offset, NULL, 10) - seg->url_offset + 1;
-    }
+    dash_ref_urllist(urls);
+    urls->nb = nb_urls;
 
-    return seg;
+    return urls;
 }
 
-static int parse_manifest_segmenturlnode(AVFormatContext *s, struct representation *rep,
-                                         xmlNodePtr fragmenturl_node,
-                                         xmlNodePtr *baseurl_nodes,
-                                         char *rep_id_val,
-                                         char *rep_bandwidth_val)
+static av_cold int dash_parse_baseurl(AVFormatContext *s,
+                                      DASHURLList **urls,
+                                      xmlNodePtr node)
 {
+    int ret = 0;
     DASHContext *c = s->priv_data;
-    char *initialization_val = NULL;
-    char *media_val = NULL;
-    char *range_val = NULL;
-    int max_url_size = c ? c->max_url_size: MAX_URL_SIZE;
-    int err;
-
-    if (!av_strcasecmp(fragmenturl_node->name, "Initialization")) {
-        initialization_val = xmlGetProp(fragmenturl_node, "sourceURL");
-        range_val = xmlGetProp(fragmenturl_node, "range");
-        if (initialization_val || range_val) {
-            free_fragment(&rep->init_section);
-            rep->init_section = get_Fragment(range_val);
-            xmlFree(range_val);
-            if (!rep->init_section) {
-                xmlFree(initialization_val);
-                return AVERROR(ENOMEM);
-            }
-            rep->init_section->url = get_content_url(baseurl_nodes, 4,
-                                                     max_url_size,
-                                                     rep_id_val,
-                                                     rep_bandwidth_val,
-                                                     initialization_val);
-            xmlFree(initialization_val);
-            if (!rep->init_section->url) {
-                av_freep(&rep->init_section);
-                return AVERROR(ENOMEM);
-            }
-        }
-    } else if (!av_strcasecmp(fragmenturl_node->name, "SegmentURL")) {
-        media_val = xmlGetProp(fragmenturl_node, "media");
-        range_val = xmlGetProp(fragmenturl_node, "mediaRange");
-        if (media_val || range_val) {
-            struct fragment *seg = get_Fragment(range_val);
-            xmlFree(range_val);
-            if (!seg) {
-                xmlFree(media_val);
-                return AVERROR(ENOMEM);
-            }
-            seg->url = get_content_url(baseurl_nodes, 4,
-                                       max_url_size,
-                                       rep_id_val,
-                                       rep_bandwidth_val,
-                                       media_val);
-            xmlFree(media_val);
-            if (!seg->url) {
-                av_free(seg);
-                return AVERROR(ENOMEM);
-            }
-            err = av_dynarray_add_nofree(&rep->fragments, &rep->n_fragments, seg);
-            if (err < 0) {
-                free_fragment(&seg);
-                return err;
-            }
-        }
-    }
+    char *url_chunk = NULL;
+    char *resolved_url = NULL;
+    DASHURLList *new_urls = NULL;
+    int is_absolute;
+    char *base_url;
 
-    return 0;
-}
+    if (!(url_chunk = xmlNodeGetContent(node)))
+        return AVERROR(ENOMEM);
 
-static int parse_manifest_segmenttimeline(AVFormatContext *s, struct representation *rep,
-                                          xmlNodePtr fragment_timeline_node)
-{
-    xmlAttrPtr attr = NULL;
-    char *val  = NULL;
-    int err;
+    base_url = (*urls)->elems[0];
+    if ((ret = ff_make_absolute_urla(&resolved_url, base_url, url_chunk)) < 0)
+        goto out;
 
-    if (!av_strcasecmp(fragment_timeline_node->name, "S")) {
-        struct timeline *tml = av_mallocz(sizeof(struct timeline));
-        if (!tml) {
-            return AVERROR(ENOMEM);
-        }
-        attr = fragment_timeline_node->properties;
-        while (attr) {
-            val = xmlGetProp(fragment_timeline_node, attr->name);
+    if (dash_urllist_has(*urls, resolved_url))
+        goto out;
 
-            if (!val) {
-                av_log(s, AV_LOG_WARNING, "parse_manifest_segmenttimeline attr->name = %s val is NULL\n", attr->name);
-                continue;
-            }
+    is_absolute = !strcmp(resolved_url, url_chunk);
 
-            if (!av_strcasecmp(attr->name, "t")) {
-                tml->starttime = (int64_t)strtoll(val, NULL, 10);
-            } else if (!av_strcasecmp(attr->name, "r")) {
-                tml->repeat =(int64_t) strtoll(val, NULL, 10);
-            } else if (!av_strcasecmp(attr->name, "d")) {
-                tml->duration = (int64_t)strtoll(val, NULL, 10);
+    if (1 == (*urls)->refcount) {
+        /* If we own the instance, it means that this node is an alternative
+         * BaseURL. */
+        if (is_absolute) {
+            void *p;
+
+            if ((p = av_realloc(*urls, offsetof(DASHURLList, elems[(*urls)->nb + 1])))) {
+                /* Put the new URL at a random place. Absolute addresses most
+                 * commonly mean different servers/CDNs, so we can help a
+                 * little bit on load-balancing. */
+                unsigned to_index;
+
+                *urls = p;
+                to_index = av_lfg_get(&c->rnd) % ((*urls)->nb + 1);
+                (*urls)->elems[(*urls)->nb++] = (*urls)->elems[to_index];
+                (*urls)->elems[to_index] = resolved_url, resolved_url = NULL;
             }
-            attr = attr->next;
-            xmlFree(val);
+        } else {
+            /* We do not want to explode URL list so we ignore relative
+             * alternative URLs. Also, using different paths on the same
+             * server does not really makes sense. */
+        }
+    } else {
+        /* Either add a single absolute URL to the list or in case of a
+         * relative BaseURL combine it with every parent URL. */
+        if (!(new_urls = dash_new_urllist(is_absolute ? 1 : (*urls)->nb))) {
+            ret = AVERROR(ENOMEM);
+            goto out;
         }
-        err = av_dynarray_add_nofree(&rep->timelines, &rep->n_timelines, tml);
-        if (err < 0) {
-            av_free(tml);
-            return err;
+
+        /* We have already done the first one at the top. */
+        new_urls->elems[0] = resolved_url, resolved_url = NULL;
+        if (!is_absolute) {
+            for (unsigned i = 1; i < (*urls)->nb; ++i)
+                if (!(ret = ff_make_absolute_urla(&new_urls->elems[i], (*urls)->elems[i], url_chunk)))
+                    goto out;
         }
+
+        /* Replace URL list of current level with the modified one. */
+        dash_unref_urllist(*urls);
+        *urls = new_urls;
+        new_urls = NULL;
     }
 
+out:
+    xmlFree(url_chunk);
+    av_free(resolved_url);
+    dash_unref_urllist(new_urls);
+    return ret;
+}
+
+static av_cold int dash_parse_mimetype(DASHParameters *par, const char *value)
+{
+    if (!strncmp(value, "video/", 6))
+        par->codec_type = AVMEDIA_TYPE_VIDEO;
+    else if (!strncmp(value, "audio/", 6))
+        par->codec_type = AVMEDIA_TYPE_AUDIO;
+    else if (!strncmp(value, "text/", 5))
+        par->codec_type = AVMEDIA_TYPE_SUBTITLE;
+    else
+        return 1;
+
     return 0;
 }
 
-static int resolve_content_path(AVFormatContext *s, const char *url, int *max_url_size, xmlNodePtr *baseurl_nodes, int n_baseurl_nodes)
-{
-    char *tmp_str = NULL;
-    char *path = NULL;
-    char *mpdName = NULL;
-    xmlNodePtr node = NULL;
-    char *baseurl = NULL;
-    char *root_url = NULL;
-    char *text = NULL;
-    char *tmp = NULL;
-    int isRootHttp = 0;
-    char token ='/';
-    int start =  0;
-    int rootId = 0;
-    int updated = 0;
-    int size = 0;
-    int i;
-    int tmp_max_url_size = strlen(url);
-
-    for (i = n_baseurl_nodes-1; i >= 0 ; i--) {
-        text = xmlNodeGetContent(baseurl_nodes[i]);
-        if (!text)
-            continue;
-        tmp_max_url_size += strlen(text);
-        if (ishttp(text)) {
-            xmlFree(text);
-            break;
-        }
-        xmlFree(text);
+static av_cold int dash_parse_contenttype(AVFormatContext *s,
+                                          DASHParameters *par,
+                                          const xmlChar *value)
+{
+    if (!strcmp(value, "video"))
+        par->codec_type = AVMEDIA_TYPE_VIDEO;
+    else if (!strcmp(value, "audio"))
+        par->codec_type = AVMEDIA_TYPE_AUDIO;
+    else {
+        par->codec_type = AVMEDIA_TYPE_UNKNOWN;
+        return 1;
     }
 
-    tmp_max_url_size = aligned(tmp_max_url_size);
-    text = av_mallocz(tmp_max_url_size);
-    if (!text) {
-        updated = AVERROR(ENOMEM);
-        goto end;
-    }
-    av_strlcpy(text, url, strlen(url)+1);
-    tmp = text;
-    while (mpdName = av_strtok(tmp, "/", &tmp))  {
-        size = strlen(mpdName);
-    }
-    av_free(text);
+    return 0;
+}
 
-    path = av_mallocz(tmp_max_url_size);
-    tmp_str = av_mallocz(tmp_max_url_size);
-    if (!tmp_str || !path) {
-        updated = AVERROR(ENOMEM);
-        goto end;
+static av_cold int dash_parse_codecs(AVFormatContext *s,
+                                     DASHParameters *par,
+                                     const xmlChar *value)
+{
+    int n;
+    char type;
+    int flags;
+
+    /* https://developer.mozilla.org/en-US/docs/Web/Media/Formats/codecs_parameter */
+    /* https://tools.ietf.org/html/rfc6381 */
+    if (3 == av_sscanf(value, "mp4%c.%d.%d%n", &type, &par->level, &par->profile, &n) &&
+        !value[n])
+    {
+        switch (type) {
+        case 'a': par->codec_type = AVMEDIA_TYPE_AUDIO; break;
+        case 'v': par->codec_type = AVMEDIA_TYPE_VIDEO; break;
+        default: return 1;
+        }
+
+    } else if (3 == av_sscanf(value, "avc1"/* avcoti */".%02x%02x%02x%n",
+                              &par->profile, &flags, &par->level, &n) &&
+               !value[n])
+    {
+        par->codec_type = AVMEDIA_TYPE_VIDEO;
+        par->codec_id = AV_CODEC_ID_H264;
+        par->profile |= (unsigned)flags << 7;
+    } else if (av_sscanf(value, "hev1.%n", &n), n == 5)
+    {
+        par->codec_id = AV_CODEC_ID_HEVC;
+    } else {
+        par->codec_id = AV_CODEC_ID_NONE;
+        return 1;
     }
 
-    av_strlcpy (path, url, strlen(url) - size + 1);
-    for (rootId = n_baseurl_nodes - 1; rootId > 0; rootId --) {
-        if (!(node = baseurl_nodes[rootId])) {
-            continue;
-        }
-        text = xmlNodeGetContent(node);
-        if (ishttp(text)) {
-            xmlFree(text);
-            break;
-        }
-        xmlFree(text);
-    }
+    return 0;
+}
 
-    node = baseurl_nodes[rootId];
-    baseurl = xmlNodeGetContent(node);
-    root_url = (av_strcasecmp(baseurl, "")) ? baseurl : path;
-    if (node) {
-        xmlNodeSetContent(node, root_url);
-        updated = 1;
+static av_cold int dash_parse_scantype(AVFormatContext *s,
+                                       DASHParameters *par,
+                                       const xmlChar *value)
+{
+    if (!strcmp(value, "progressive")) {
+        par->field_order = AV_FIELD_PROGRESSIVE;
+    } else {
+        par->field_order = AV_FIELD_UNKNOWN;
+        return 1;
     }
 
-    size = strlen(root_url);
-    isRootHttp = ishttp(root_url);
+    return 0;
+}
 
-    if (size > 0 && root_url[size - 1] != token) {
-        av_strlcat(root_url, "/", size + 2);
-        size += 2;
-    }
+static av_cold int dash_parse_parameters(AVFormatContext *s,
+                                         DASHParameters *par,
+                                         xmlAttrPtr attr,
+                                         const xmlChar *value)
+{
+    if (!strcmp(attr->name, "height"))
+        (void)av_sscanf(value, "%d", &par->height);
+    else if (!strcmp(attr->name, "width"))
+        (void)av_sscanf(value, "%d", &par->width);
+    else if (!strcmp(attr->name, "mimeType"))
+        return dash_parse_mimetype(par, value);
+    else if (!strcmp(attr->name, "audioSamplingRate"))
+        (void)av_sscanf(value, "%d", &par->sample_rate);
+    else if (!strcmp(attr->name, "par"))
+        /* Ignore. */;
+    else if (!strcmp(attr->name, "sar"))
+        (void)av_parse_ratio(&par->sample_aspect_ratio, value, INT_MAX, AV_LOG_ERROR, s);
+    else if (!strcmp(attr->name, "frameRate"))
+        (void)av_sscanf(value, "%d", &par->frame_rate);
+    else if (!strcmp(attr->name, "codecs"))
+        return dash_parse_codecs(s, par, value);
+    else if (!strcmp(attr->name, "scanType"))
+        return dash_parse_scantype(s, par, value);
+    else if (!strcmp(attr->name, "contentType"))
+        return dash_parse_contenttype(s, par, value);
+    else
+        return 1;
 
-    for (i = 0; i < n_baseurl_nodes; ++i) {
-        if (i == rootId) {
-            continue;
-        }
-        text = xmlNodeGetContent(baseurl_nodes[i]);
-        if (text && !av_strstart(text, "/", NULL)) {
-            memset(tmp_str, 0, strlen(tmp_str));
-            if (!ishttp(text) && isRootHttp) {
-                av_strlcpy(tmp_str, root_url, size + 1);
-            }
-            start = (text[0] == token);
-            if (start && av_stristr(tmp_str, text)) {
-                char *p = tmp_str;
-                if (!av_strncasecmp(tmp_str, "http://", 7)) {
-                    p += 7;
-                } else if (!av_strncasecmp(tmp_str, "https://", 8)) {
-                    p += 8;
-                }
-                p = strchr(p, '/');
-                memset(p + 1, 0, strlen(p));
-            }
-            av_strlcat(tmp_str, text + start, tmp_max_url_size);
-            xmlNodeSetContent(baseurl_nodes[i], tmp_str);
-            updated = 1;
-            xmlFree(text);
-        }
+    return 0;
+}
+
+static av_cold int dash_parse_audiochannelconfiguration(AVFormatContext *s,
+                                                        DASHParameters *par,
+                                                        xmlNodePtr node)
+{
+    int ret = 0;
+    DASHScheme scheme;
+
+    if ((ret = dash_parse_scheme(s, &scheme, 1, node)) < 0)
+        goto out;
+
+    par->channels = 0;
+    par->channel_layout = 0;
+    par->matrix_encoding = AV_MATRIX_ENCODING_NONE;
+
+    /* https://testassets.dashif.org/#testvector/details/586fb3879ae9045678eacd10 */
+    if (!strcmp(scheme.scheme_id, "urn:dolby:dash:audio_channel_configuration:2011") ||
+        !strcmp(scheme.scheme_id, "tag:dolby.com,2014:dash:audio_channel_configuration:2011"))
+    {
+        par->matrix_encoding = AV_MATRIX_ENCODING_DOLBY;
+        (void)av_get_extended_channel_layout(scheme.value, &par->channel_layout, &par->channels);
+    } else if (!strcmp(scheme.scheme_id, "urn:mpeg:dash:23003:3:audio_channel_configuration:2011")) {
+        (void)av_sscanf(scheme.value, "%d", &par->channels);
+        par->channel_layout = av_get_default_channel_layout(par->channels);
+    } else {
+        (void)av_get_extended_channel_layout(scheme.value, &par->channel_layout, &par->channels);
+        dash_log_unknown_scheme(s, &scheme);
+    }
+
+out:
+    dash_free_scheme(&scheme);
+    return ret;
+}
+
+static av_cold int dash_parse_assetidentifier(AVFormatContext *s,
+                                              DASHPeriod *period,
+                                              xmlNodePtr node)
+{
+    int ret = 0;
+    DASHScheme scheme;
+
+    if ((ret = dash_parse_scheme(s, &scheme, 1, node)) < 0)
+        goto out;
+
+    if (!strcmp(scheme.scheme_id, "urn:org:dashif:asset-id:2013")) {
+        av_dict_set(&period->metadata, "asset_identifier", scheme.value, 0);
+    } else {
+        dash_log_unknown_scheme(s, &scheme);
+    }
+
+out:
+    dash_free_scheme(&scheme);
+    return ret;
+}
+
+static av_cold int dash_parse_viewpoint(AVFormatContext *s,
+                                        DASHAdaptationSet *as,
+                                        xmlNodePtr node)
+{
+    int ret = 0;
+    DASHScheme scheme;
+
+    if ((ret = dash_parse_scheme(s, &scheme, 1, node)) < 0)
+        goto out;
+
+    /* https://testassets.dashif.org/#testvector/details/5cde78e4a5eeda55aa663101 */
+    if (!strcmp(scheme.scheme_id, "urn:mpeg:dash:viewpoint:2011")) {
+        av_dict_set(&as->metadata, "viewpoint", scheme.value, 0);
+    } else {
+        dash_log_unknown_scheme(s, &scheme);
     }
 
-end:
-    if (tmp_max_url_size > *max_url_size) {
-        *max_url_size = tmp_max_url_size;
+out:
+    dash_free_scheme(&scheme);
+    return ret;
+}
+
+static av_cold void dash_sync_time(AVFormatContext *s, const xmlChar *value)
+{
+    DASHContext *c = s->priv_data;
+    int ret = 0;
+
+    switch (c->utc_timing) {
+    case DASH_UTC_TIMING_LOCAL:
+    default:
+        ret = 1;
+        break;
+    case DASH_UTC_TIMING_HTTP_XSDATE:
+    case DASH_UTC_TIMING_HTTP_ISO:
+    case DASH_UTC_TIMING_HTTP_NTP:
+    case DASH_UTC_TIMING_NTP:
+    case DASH_UTC_TIMING_HTTP_HEAD:
+    case DASH_UTC_TIMING_DIRECT:
+        ret = AVERROR_PATCHWELCOME;
+        break;
     }
-    av_free(path);
-    av_free(tmp_str);
-    xmlFree(baseurl);
-    return updated;
 
+    if (!ret) {
+        av_log(s, AV_LOG_DEBUG, "Time synchronized: %lf s\n",
+               (double)c->time_diff / AV_TIME_BASE);
+        c->utc_timing = -c->utc_timing;
+    } else if (ret < 0) {
+        av_log(s, AV_LOG_ERROR, "Failed to synchronized time: %s\n",
+               av_err2str(ret));
+    }
 }
 
-static int parse_manifest_representation(AVFormatContext *s, const char *url,
-                                         xmlNodePtr node,
-                                         xmlNodePtr adaptionset_node,
-                                         xmlNodePtr mpd_baseurl_node,
-                                         xmlNodePtr period_baseurl_node,
-                                         xmlNodePtr period_segmenttemplate_node,
-                                         xmlNodePtr period_segmentlist_node,
-                                         xmlNodePtr fragment_template_node,
-                                         xmlNodePtr content_component_node,
-                                         xmlNodePtr adaptionset_baseurl_node,
-                                         xmlNodePtr adaptionset_segmentlist_node,
-                                         xmlNodePtr adaptionset_supplementalproperty_node)
+static av_cold int dash_parse_utctiming(AVFormatContext *s,
+                                        xmlNodePtr node)
 {
-    int32_t ret = 0;
+    int ret = 0;
     DASHContext *c = s->priv_data;
-    struct representation *rep = NULL;
-    struct fragment *seg = NULL;
-    xmlNodePtr representation_segmenttemplate_node = NULL;
-    xmlNodePtr representation_baseurl_node = NULL;
-    xmlNodePtr representation_segmentlist_node = NULL;
-    xmlNodePtr segmentlists_tab[3];
-    xmlNodePtr fragment_timeline_node = NULL;
-    xmlNodePtr fragment_templates_tab[5];
-    char *val = NULL;
-    xmlNodePtr baseurl_nodes[4];
-    xmlNodePtr representation_node = node;
-    char *rep_bandwidth_val;
-    enum AVMediaType type = AVMEDIA_TYPE_UNKNOWN;
-
-    // try get information from representation
-    if (type == AVMEDIA_TYPE_UNKNOWN)
-        type = get_content_type(representation_node);
-    // try get information from contentComponen
-    if (type == AVMEDIA_TYPE_UNKNOWN)
-        type = get_content_type(content_component_node);
-    // try get information from adaption set
-    if (type == AVMEDIA_TYPE_UNKNOWN)
-        type = get_content_type(adaptionset_node);
-    if (type != AVMEDIA_TYPE_VIDEO && type != AVMEDIA_TYPE_AUDIO &&
-        type != AVMEDIA_TYPE_SUBTITLE) {
-        av_log(s, AV_LOG_VERBOSE, "Parsing '%s' - skipp not supported representation type\n", url);
+    DASHScheme scheme;
+    int utc_timing = c->utc_timing;
+
+    if ((ret = dash_parse_scheme(s, &scheme, 0, node)) < 0)
+        goto out;
+
+    c->utc_timing = DASH_UTC_TIMING_LOCAL;
+
+    if (0);
+#define PARSE(name, scheme_name) \
+    else if (!strcmp(scheme.scheme_id, "urn:mpeg:dash:utc:"scheme_name":2014")) \
+        c->utc_timing = DASH_UTC_TIMING_##name
+    PARSE(HTTP_XSDATE, "http-xsdate");
+    PARSE(HTTP_ISO,    "http-iso");
+    PARSE(HTTP_NTP,    "http-ntp");
+    PARSE(NTP,         "ntp");
+    PARSE(HTTP_HEAD,   "http-head");
+    PARSE(DIRECT,      "direct");
+#undef PARSE
+    else
+        dash_log_unknown_scheme(s, &scheme);
+
+    if (c->utc_timing == -utc_timing)
+        c->utc_timing = utc_timing;
+
+    dash_sync_time(s, scheme.value);
+
+out:
+    dash_free_scheme(&scheme);
+    return ret;
+}
+
+static av_cold int dash_parse_role(AVFormatContext *s,
+                                   DASHParameters *par,
+                                   xmlNodePtr node)
+{
+    int ret = 0;
+    DASHScheme scheme;
+
+    if ((ret = dash_parse_scheme(s, &scheme, 1, node)) < 0)
+        goto out;
+
+    /* https://testassets.dashif.org/#feature/details/588a48c27459f8cb201b881b */
+    if (!strcmp(scheme.scheme_id, "urn:mpeg:dash:role:2011")) {
+        if (!strcmp(scheme.value, "main"))
+            par->disposition |= AV_DISPOSITION_DEFAULT;
+        else if (!strcmp(scheme.value, "alternate"))
+            par->disposition &= ~AV_DISPOSITION_DEFAULT;
+        else if (!strcmp(scheme.value, "original"))
+            par->disposition |= AV_DISPOSITION_ORIGINAL;
+        else if (!strcmp(scheme.value, "dub"))
+            par->disposition |= AV_DISPOSITION_DUB;
+        else if (!strcmp(scheme.value, "subtitle"))
+            par->codec_type = AVMEDIA_TYPE_SUBTITLE;
+    } else {
+        dash_log_unknown_scheme(s, &scheme);
+    }
+
+out:
+    dash_free_scheme(&scheme);
+    return ret;
+}
+
+static av_cold int dash_parse_property(AVFormatContext *s,
+                                       DASHAdaptationSet *as,
+                                       DASHRepresentationPeriod *rep,
+                                       xmlNodePtr node)
+{
+    int ret = 0;
+    DASHContext *c = s->priv_data;
+    DASHScheme scheme;
+
+    if ((ret = dash_parse_scheme(s, &scheme, 1, node)) < 0)
+        goto out;
+
+    /* https://testassets.dashif.org/#feature/details/588a48c27459f8cb201b881b */
+    if ((!as && !rep) && !strcmp(scheme.scheme_id, "urn:mpeg:dash:chaining:2016")) {
+        xml_free(c->chain_next_location);
+        c->chain_next_location = scheme.value;
+        scheme.value = NULL;
+    } else if ((!as && !rep) && !strcmp(scheme.scheme_id, "urn:mpeg:dash:fallback:2016")) {
+        xml_free(c->fallback_location);
+        c->fallback_location = scheme.value;
+        scheme.value = NULL;
+    } else {
+        dash_log_unknown_scheme(s, &scheme);
+    }
+
+out:
+    dash_free_scheme(&scheme);
+    return ret;
+}
+
+static av_cold int dash_check_existing_timeline(AVFormatContext *s, DASHTimeline **out_timeline, xmlNodePtr timeline_node)
+{
+    if (!*out_timeline)
         return 0;
+
+    av_log(s, AV_LOG_ERROR, "Multiple timelines specified\n");
+    dash_log_unknown_child(s, timeline_node);
+
+    return AVERROR_INVALIDDATA;
+}
+
+static int dash_parse_segmentlist(AVFormatContext *s,
+                                  DASHPeriod *period,
+                                  DASHTimeline **out_timeline,
+                                  xmlNodePtr node)
+{
+    int nb_segments = 0;
+    int64_t duration = 0;
+    int64_t timescale = 1;
+    DASHTimeline *timeline = NULL;
+    DASHSegment *g;
+    int ret = 0;
+
+    if ((ret = dash_check_existing_timeline(s, out_timeline, node) < 0))
+        return ret;
+
+    xml_for_each_attr {
+        if (!strcmp(attr->name, "duration"))
+            (void)av_sscanf(value, "%"SCNd64, &duration);
+        else if (!strcmp(attr->name, "timescale"))
+            (void)av_sscanf(value, "%"SCNd64, &timescale);
+        else
+            dash_log_unknown_attr(s, attr, value);
     }
 
-    // convert selected representation to our internal struct
-    rep = av_mallocz(sizeof(struct representation));
-    if (!rep)
-        return AVERROR(ENOMEM);
-    if (c->adaptionset_lang) {
-        rep->lang = av_strdup(c->adaptionset_lang);
-        if (!rep->lang) {
-            av_log(s, AV_LOG_ERROR, "alloc language memory failure\n");
-            av_freep(&rep);
-            return AVERROR(ENOMEM);
-        }
+    xml_for_each_child {
+        if (!strcmp(child->name, "SegmentURL"))
+            ++nb_segments;
+        else
+            dash_log_unknown_child(s, child);
     }
-    rep->parent = s;
-    representation_segmenttemplate_node = find_child_node_by_name(representation_node, "SegmentTemplate");
-    representation_baseurl_node = find_child_node_by_name(representation_node, "BaseURL");
-    representation_segmentlist_node = find_child_node_by_name(representation_node, "SegmentList");
-    rep_bandwidth_val = xmlGetProp(representation_node, "bandwidth");
-    val               = xmlGetProp(representation_node, "id");
-    if (val) {
-        rep->id = av_strdup(val);
-        xmlFree(val);
-        if (!rep->id)
-            goto enomem;
-    }
-
-    baseurl_nodes[0] = mpd_baseurl_node;
-    baseurl_nodes[1] = period_baseurl_node;
-    baseurl_nodes[2] = adaptionset_baseurl_node;
-    baseurl_nodes[3] = representation_baseurl_node;
-
-    ret = resolve_content_path(s, url, &c->max_url_size, baseurl_nodes, 4);
-    c->max_url_size = aligned(c->max_url_size
-                              + (rep->id ? strlen(rep->id) : 0)
-                              + (rep_bandwidth_val ? strlen(rep_bandwidth_val) : 0));
-    if (ret == AVERROR(ENOMEM) || ret == 0)
-        goto free;
-    if (representation_segmenttemplate_node || fragment_template_node || period_segmenttemplate_node) {
-        fragment_timeline_node = NULL;
-        fragment_templates_tab[0] = representation_segmenttemplate_node;
-        fragment_templates_tab[1] = adaptionset_segmentlist_node;
-        fragment_templates_tab[2] = fragment_template_node;
-        fragment_templates_tab[3] = period_segmenttemplate_node;
-        fragment_templates_tab[4] = period_segmentlist_node;
-
-        val = get_val_from_nodes_tab(fragment_templates_tab, 4, "initialization");
-        if (val) {
-            rep->init_section = av_mallocz(sizeof(struct fragment));
-            if (!rep->init_section) {
-                xmlFree(val);
-                goto enomem;
-            }
-            c->max_url_size = aligned(c->max_url_size  + strlen(val));
-            rep->init_section->url = get_content_url(baseurl_nodes, 4,
-                                                     c->max_url_size, rep->id,
-                                                     rep_bandwidth_val, val);
-            xmlFree(val);
-            if (!rep->init_section->url)
-                goto enomem;
-            rep->init_section->size = -1;
-        }
-        val = get_val_from_nodes_tab(fragment_templates_tab, 4, "media");
-        if (val) {
-            c->max_url_size = aligned(c->max_url_size  + strlen(val));
-            rep->url_template = get_content_url(baseurl_nodes, 4,
-                                                c->max_url_size, rep->id,
-                                                rep_bandwidth_val, val);
-            xmlFree(val);
-        }
-        val = get_val_from_nodes_tab(fragment_templates_tab, 4, "presentationTimeOffset");
-        if (val) {
-            rep->presentation_timeoffset = (int64_t) strtoll(val, NULL, 10);
-            av_log(s, AV_LOG_TRACE, "rep->presentation_timeoffset = [%"PRId64"]\n", rep->presentation_timeoffset);
-            xmlFree(val);
-        }
-        val = get_val_from_nodes_tab(fragment_templates_tab, 4, "duration");
-        if (val) {
-            rep->fragment_duration = (int64_t) strtoll(val, NULL, 10);
-            av_log(s, AV_LOG_TRACE, "rep->fragment_duration = [%"PRId64"]\n", rep->fragment_duration);
-            xmlFree(val);
-        }
-        val = get_val_from_nodes_tab(fragment_templates_tab, 4, "timescale");
-        if (val) {
-            rep->fragment_timescale = (int64_t) strtoll(val, NULL, 10);
-            av_log(s, AV_LOG_TRACE, "rep->fragment_timescale = [%"PRId64"]\n", rep->fragment_timescale);
-            xmlFree(val);
+
+    if (!(timeline = av_mallocz(offsetof(DASHTimeline, u.segments.elems[nb_segments])))) {
+        ret = AVERROR(ENOMEM);
+        goto out;
+    }
+    dash_ref_timeline(timeline);
+    timeline->type = TIMELINE_SEGMENTS;
+    timeline->u.segments.nb = nb_segments;
+    g = &timeline->u.segments.elems[0];
+
+    xml_for_each_child {
+        xmlNodePtr node = child;
+
+        if (strcmp(node->name, "SegmentURL"))
+            continue;
+
+        xml_for_each_attr {
+            if (!strcmp(attr->name, "media")) {
+                g->url = value;
+                value = NULL;
+            } else
+                dash_log_unknown_attr(s, attr, value);
         }
-        val = get_val_from_nodes_tab(fragment_templates_tab, 4, "startNumber");
-        if (val) {
-            rep->start_number = rep->first_seq_no = (int64_t) strtoll(val, NULL, 10);
-            av_log(s, AV_LOG_TRACE, "rep->first_seq_no = [%"PRId64"]\n", rep->first_seq_no);
-            xmlFree(val);
+        if (!g->url) {
+            dash_log_missing_attr(s, node, "media");
+            ret = AVERROR_INVALIDDATA;
+            goto out;
         }
-        if (adaptionset_supplementalproperty_node) {
-            if (!av_strcasecmp(xmlGetProp(adaptionset_supplementalproperty_node,"schemeIdUri"), "http://dashif.org/guidelines/last-segment-number")) {
-                val = xmlGetProp(adaptionset_supplementalproperty_node,"value");
-                if (!val) {
-                    av_log(s, AV_LOG_ERROR, "Missing value attribute in adaptionset_supplementalproperty_node\n");
-                } else {
-                    rep->last_seq_no =(int64_t) strtoll(val, NULL, 10) - 1;
-                    xmlFree(val);
+
+        ++g;
+    }
+
+    *out_timeline = dash_ref_timeline(timeline);
+
+out:
+    dash_unref_timeline(timeline);
+    return ret;
+}
+
+static av_cold int dash_parse_segmenttimeline(AVFormatContext *s,
+                                              DASHPeriod *period,
+                                              uint64_t start_number,
+                                              DASHTimeline **out_timeline,
+                                              xmlNodePtr node)
+{
+    int ret = 0;
+    unsigned nb_selems = 0;
+    DASHSegmentTemplate *g;
+    DASHTimeline *timeline;
+    int64_t start_ts = 0;
+
+    if ((ret = dash_check_existing_timeline(s, out_timeline, node) < 0))
+        return ret;
+
+    xml_for_each_attr {
+        dash_log_unknown_attr(s, attr, value);
+    }
+
+    xml_for_each_child {
+        if (!strcmp(child->name, "S"))
+            ++nb_selems;
+        else
+            dash_log_unknown_child(s, child);
+    }
+
+    if (!(timeline = av_malloc(offsetof(DASHTimeline, u.templates.elems[nb_selems])))) {
+        ret = AVERROR(ENOMEM);
+        goto out;
+    }
+    memset(timeline, 0, offsetof(DASHTimeline, u.templates.elems[0]));
+    dash_ref_timeline(timeline);
+    timeline->type = TIMELINE_TEMPLATES;
+    timeline->u.templates.nb = nb_selems;
+    g = &timeline->u.templates.elems[0];
+
+    xml_for_each_child {
+        xmlNodePtr node = child;
+
+        if (strcmp(node->name, "S"))
+            continue;
+
+        *g = (DASHSegmentTemplate){
+            .start_ts = start_ts,
+            .number = start_number
+        };
+
+        xml_for_each_attr {
+            int64_t num = 0;
+
+            (void)av_sscanf(value, "%"SCNd64, &num);
+
+            if (!strcmp(attr->name, "t")) {
+                /* Muste be increasing. */
+                if (num < start_ts) {
+                    dash_log_invalid_attr_value(s, attr, value);
+                    ret = AVERROR_INVALIDDATA;
+                    goto out;
                 }
-            }
-        }
 
-        fragment_timeline_node = find_child_node_by_name(representation_segmenttemplate_node, "SegmentTimeline");
-
-        if (!fragment_timeline_node)
-            fragment_timeline_node = find_child_node_by_name(fragment_template_node, "SegmentTimeline");
-        if (!fragment_timeline_node)
-            fragment_timeline_node = find_child_node_by_name(adaptionset_segmentlist_node, "SegmentTimeline");
-        if (!fragment_timeline_node)
-            fragment_timeline_node = find_child_node_by_name(period_segmentlist_node, "SegmentTimeline");
-        if (fragment_timeline_node) {
-            fragment_timeline_node = xmlFirstElementChild(fragment_timeline_node);
-            while (fragment_timeline_node) {
-                ret = parse_manifest_segmenttimeline(s, rep, fragment_timeline_node);
-                if (ret < 0)
-                    goto free;
-                fragment_timeline_node = xmlNextElementSibling(fragment_timeline_node);
+                g->start_ts = num;
+            } else if (!strcmp(attr->name, "n"))
+                g->number = num;
+            else if (!strcmp(attr->name, "r"))
+                g->repeat = num;
+            else if (!strcmp(attr->name, "d")) {
+                g->duration = num;
+
+                if (g->duration <= 0) {
+                    dash_log_invalid_attr_value(s, attr, value);
+                    ret = AVERROR_INVALIDDATA;
+                    goto out;
+                }
+            } else {
+                dash_log_unknown_attr(s, attr, value);
             }
         }
-    } else if (representation_baseurl_node && !representation_segmentlist_node) {
-        seg = av_mallocz(sizeof(struct fragment));
-        if (!seg)
-            goto enomem;
-        ret = av_dynarray_add_nofree(&rep->fragments, &rep->n_fragments, seg);
-        if (ret < 0) {
-            av_free(seg);
-            goto free;
-        }
-        seg->url = get_content_url(baseurl_nodes, 4, c->max_url_size,
-                                   rep->id, rep_bandwidth_val, NULL);
-        if (!seg->url)
-            goto enomem;
-        seg->size = -1;
-    } else if (representation_segmentlist_node) {
-        // TODO: https://www.brendanlong.com/the-structure-of-an-mpeg-dash-mpd.html
-        // http://www-itec.uni-klu.ac.at/dash/ddash/mpdGenerator.php?fragmentlength=15&type=full
-        xmlNodePtr fragmenturl_node = NULL;
-        segmentlists_tab[0] = representation_segmentlist_node;
-        segmentlists_tab[1] = adaptionset_segmentlist_node;
-        segmentlists_tab[2] = period_segmentlist_node;
-
-        val = get_val_from_nodes_tab(segmentlists_tab, 3, "duration");
-        if (val) {
-            rep->fragment_duration = (int64_t) strtoll(val, NULL, 10);
-            av_log(s, AV_LOG_TRACE, "rep->fragment_duration = [%"PRId64"]\n", rep->fragment_duration);
-            xmlFree(val);
-        }
-        val = get_val_from_nodes_tab(segmentlists_tab, 3, "timescale");
-        if (val) {
-            rep->fragment_timescale = (int64_t) strtoll(val, NULL, 10);
-            av_log(s, AV_LOG_TRACE, "rep->fragment_timescale = [%"PRId64"]\n", rep->fragment_timescale);
-            xmlFree(val);
-        }
-        val = get_val_from_nodes_tab(segmentlists_tab, 3, "startNumber");
-        if (val) {
-            rep->start_number = rep->first_seq_no = (int64_t) strtoll(val, NULL, 10);
-            av_log(s, AV_LOG_TRACE, "rep->first_seq_no = [%"PRId64"]\n", rep->first_seq_no);
-            xmlFree(val);
-        }
 
-        fragmenturl_node = xmlFirstElementChild(representation_segmentlist_node);
-        while (fragmenturl_node) {
-            ret = parse_manifest_segmenturlnode(s, rep, fragmenturl_node,
-                                                baseurl_nodes, rep->id,
-                                                rep_bandwidth_val);
-            if (ret < 0)
-                goto free;
-            fragmenturl_node = xmlNextElementSibling(fragmenturl_node);
-        }
+        start_number = g->number + (g->repeat + 1);
+        start_ts = g->start_ts + g->duration * (g->repeat + 1);
+        ++g;
+    }
+
+    *out_timeline = dash_ref_timeline(timeline);
+
+out:
+    dash_unref_timeline(timeline);
+    return ret;
+}
+
+/* One init URL and list of template arguments. */
+static av_cold int dash_parse_segmenttemplate(AVFormatContext *s,
+                                              DASHPeriod *period,
+                                              DASHTimeline **out_timeline,
+                                              xmlNodePtr node)
+{
+    int ret = 0;
+    DASHTimeline *timeline = NULL;
+    int64_t duration = -1;
+    uint64_t start_number = 1;
+    int64_t presentation_time_offset = 0;
+    int64_t timescale = 1;
+    xmlChar *init_url = NULL;
+    xmlChar *media_url = NULL;
+
+    if ((ret = dash_check_existing_timeline(s, out_timeline, node) < 0))
+        return ret;
 
-        fragment_timeline_node = find_child_node_by_name(adaptionset_segmentlist_node, "SegmentTimeline");
-        if (!fragment_timeline_node)
-            fragment_timeline_node = find_child_node_by_name(period_segmentlist_node, "SegmentTimeline");
-        if (fragment_timeline_node) {
-            fragment_timeline_node = xmlFirstElementChild(fragment_timeline_node);
-            while (fragment_timeline_node) {
-                ret = parse_manifest_segmenttimeline(s, rep, fragment_timeline_node);
-                if (ret < 0)
-                    goto free;
-                fragment_timeline_node = xmlNextElementSibling(fragment_timeline_node);
+    xml_for_each_attr {
+        if (!strcmp(attr->name, "startNumber"))
+            (void)av_sscanf(value, "%"SCNu64, &start_number);
+        else if (!strcmp(attr->name, "duration")) {
+            (void)av_sscanf(value, "%"SCNd64, &duration);
+            if (duration < 0) {
+                dash_log_invalid_attr_value(s, attr, value);
+                ret = AVERROR_INVALIDDATA;
             }
-        }
+        } else if (!strcmp(attr->name, "presentationTimeOffset"))
+            (void)av_sscanf(value, "%"SCNu64, &presentation_time_offset);
+        else if (!strcmp(attr->name, "timescale")) {
+            (void)av_sscanf(value, "%"SCNd64, &timescale);
+            if (timescale <= 0) {
+                dash_log_invalid_attr_value(s, attr, value);
+                ret = AVERROR_INVALIDDATA;
+            }
+        } else if (!strcmp(attr->name, "initialization")) {
+            init_url = value;
+            value = NULL;
+        } else if (!strcmp(attr->name, "media")) {
+            media_url = value;
+            value = NULL;
+        } else
+            dash_log_unknown_attr(s, attr, value);
+    }
+
+    /* value has to be free()'d */
+    if (ret < 0)
+        goto out;
+
+    if (!init_url || !media_url) {
+        ret = AVERROR_INVALIDDATA;
+        dash_log_missing_attr(s, node, !init_url ? "initialization" : "media");
+        goto out;
+    }
+
+    if (0 <= duration) {
+        DASHSegmentTemplate *g;
+
+        if (!(timeline = av_mallocz(offsetof(DASHTimeline, u.templates.elems[1])))) {
+            ret = AVERROR(ENOMEM);
+            goto out;
+        }
+        dash_ref_timeline(timeline);
+        timeline->type = TIMELINE_TEMPLATES;
+        timeline->u.templates.nb = 1;
+        g = &timeline->u.templates.elems[0];
+        g->start_ts = 0;
+        g->number = start_number;
+        g->repeat = INT64_MAX;
+        /* We round down in order to fetch segments more instead before than after. */
+        g->duration =  duration; /* av_rescale_rnd(duration, AV_TIME_BASE, timescale, AV_ROUND_DOWN); */
     } else {
-        av_log(s, AV_LOG_ERROR, "Unknown format of Representation node id '%s' \n",
-               rep->id ? rep->id : "");
-        goto free;
-    }
-
-    if (rep->fragment_duration > 0 && !rep->fragment_timescale)
-        rep->fragment_timescale = 1;
-    rep->bandwidth = rep_bandwidth_val ? atoi(rep_bandwidth_val) : 0;
-    rep->framerate = av_make_q(0, 0);
-    if (type == AVMEDIA_TYPE_VIDEO) {
-        char *rep_framerate_val = xmlGetProp(representation_node, "frameRate");
-        if (rep_framerate_val) {
-            ret = av_parse_video_rate(&rep->framerate, rep_framerate_val);
+        xml_for_each_child {
+            if (!strcmp(child->name, "SegmentTimeline"))
+                ret = dash_parse_segmenttimeline(s, period, start_number, &timeline, child);
+            else
+                dash_log_unknown_child(s, child);
+
             if (ret < 0)
-                av_log(s, AV_LOG_VERBOSE, "Ignoring invalid frame rate '%s'\n", rep_framerate_val);
-            xmlFree(rep_framerate_val);
+                goto out;
+        }
+
+        /* Either a SegmentTemplate@duration or a SegmentTimeline must be
+         * given. */
+        if (!timeline) {
+            av_log(s, AV_LOG_ERROR, "Missing %s/%s",
+                   node->name, "SegmentTimeline");
+            ret = AVERROR_INVALIDDATA;
+            goto out;
         }
-    }
 
-    switch (type) {
-    case AVMEDIA_TYPE_VIDEO:
-        ret = av_dynarray_add_nofree(&c->videos, &c->n_videos, rep);
-        break;
-    case AVMEDIA_TYPE_AUDIO:
-        ret = av_dynarray_add_nofree(&c->audios, &c->n_audios, rep);
-        break;
-    case AVMEDIA_TYPE_SUBTITLE:
-        ret = av_dynarray_add_nofree(&c->subtitles, &c->n_subtitles, rep);
-        break;
     }
-    if (ret < 0)
-        goto free;
 
-end:
-    if (rep_bandwidth_val)
-        xmlFree(rep_bandwidth_val);
+    timeline->duration = INT64_MAX;
+    timeline->timescale = timescale;
+    timeline->init.range = DASH_RANGE_INITIALIZER;
+    timeline->init.url = init_url;
+    init_url = NULL;
+    timeline->u.templates.master.url = media_url;
+    media_url = NULL;
+
+    timeline->u.templates.master.range = DASH_RANGE_INITIALIZER;
 
+    *out_timeline = dash_ref_timeline(timeline);
+
+out:
+    xml_free(init_url);
+    xml_free(media_url);
+    dash_unref_timeline(timeline);
     return ret;
-enomem:
-    ret = AVERROR(ENOMEM);
-free:
-    free_representation(rep);
-    goto end;
 }
 
-static int parse_manifest_adaptationset_attr(AVFormatContext *s, xmlNodePtr adaptionset_node)
+static DASHRange dash_parse_range(const char *s, AVFormatContext *log_ctx)
 {
-    DASHContext *c = s->priv_data;
+    DASHRange range = {
+        .start = 0,
+        .end = INT64_MAX
+    };
+    (void)av_sscanf(s, "%"SCNd64"-%"SCNd64, &range.start, &range.end);
+    return range;
+}
 
-    if (!adaptionset_node) {
-        av_log(s, AV_LOG_WARNING, "Cannot get AdaptionSet\n");
-        return AVERROR(EINVAL);
+static int dash_parse_segmentbase(AVFormatContext *s,
+                                  DASHPeriod *period,
+                                  DASHTimeline **out_timeline,
+                                  xmlNodePtr node)
+{
+    int ret = 0;
+    DASHSegment *g;
+    DASHTimeline *timeline;
+
+    if ((ret = dash_check_existing_timeline(s, out_timeline, node) < 0))
+        return ret;
+
+    if (!(timeline = av_mallocz(offsetof(DASHTimeline, u.segments.elems[1])))) {
+        ret = AVERROR(ENOMEM);
+        goto out;
+    }
+    dash_ref_timeline(timeline);
+    timeline->type = TIMELINE_SEGMENTS;
+    timeline->duration = INT64_MAX;
+    timeline->u.segments.nb = 1;
+    g = &timeline->u.segments.elems[0];
+
+    abort();
+    xml_for_each_child {
+        if (!strcmp(child->name, "Initalization")) {
+            xmlNodePtr node = child;
+            xml_for_each_attr {
+                if (!strcmp(attr->name, "range"))
+                    timeline->init.range = dash_parse_range(value, s);
+                else
+                    dash_log_unknown_attr(s, attr, value);
+            }
+        } else
+            dash_log_unknown_child(s, child);
     }
-    c->adaptionset_lang = xmlGetProp(adaptionset_node, "lang");
 
+    (void)g;
+
+    *out_timeline = dash_ref_timeline(timeline);
+
+out:
+    dash_unref_timeline(timeline);
     return 0;
 }
 
-static int parse_manifest_adaptationset(AVFormatContext *s, const char *url,
-                                        xmlNodePtr adaptionset_node,
-                                        xmlNodePtr mpd_baseurl_node,
-                                        xmlNodePtr period_baseurl_node,
-                                        xmlNodePtr period_segmenttemplate_node,
-                                        xmlNodePtr period_segmentlist_node)
+/**
+ * Make segment URL.
+ * @param base Absolute base path.
+ * @param template Absolute or relative path, potentially containing $ template
+ *                 arguments that will be substituted. May be NULL.
+ * @return The allocated URL that shall be av_free()d by the caller.
+ */
+static char *dash_make_url(const char *base, const char *template,
+                           /* Template arguments. */
+                           const char *$RepresentationID$,
+                           uint64_t $Number$,
+                           int64_t $Time$,
+                           uint32_t $Bandwidth$)
 {
-    int ret = 0;
-    DASHContext *c = s->priv_data;
-    xmlNodePtr fragment_template_node = NULL;
-    xmlNodePtr content_component_node = NULL;
-    xmlNodePtr adaptionset_baseurl_node = NULL;
-    xmlNodePtr adaptionset_segmentlist_node = NULL;
-    xmlNodePtr adaptionset_supplementalproperty_node = NULL;
-    xmlNodePtr node = NULL;
-
-    ret = parse_manifest_adaptationset_attr(s, adaptionset_node);
-    if (ret < 0)
-        return ret;
+    enum { MAX_DIGITS = 20 };
 
-    node = xmlFirstElementChild(adaptionset_node);
-    while (node) {
-        if (!av_strcasecmp(node->name, "SegmentTemplate")) {
-            fragment_template_node = node;
-        } else if (!av_strcasecmp(node->name, "ContentComponent")) {
-            content_component_node = node;
-        } else if (!av_strcasecmp(node->name, "BaseURL")) {
-            adaptionset_baseurl_node = node;
-        } else if (!av_strcasecmp(node->name, "SegmentList")) {
-            adaptionset_segmentlist_node = node;
-        } else if (!av_strcasecmp(node->name, "SupplementalProperty")) {
-            adaptionset_supplementalproperty_node = node;
-        } else if (!av_strcasecmp(node->name, "Representation")) {
-            ret = parse_manifest_representation(s, url, node,
-                                                adaptionset_node,
-                                                mpd_baseurl_node,
-                                                period_baseurl_node,
-                                                period_segmenttemplate_node,
-                                                period_segmentlist_node,
-                                                fragment_template_node,
-                                                content_component_node,
-                                                adaptionset_baseurl_node,
-                                                adaptionset_segmentlist_node,
-                                                adaptionset_supplementalproperty_node);
-            if (ret < 0)
-                goto err;
+    size_t base_size;
+    size_t $RepresentationID$_size = strlen($RepresentationID$);
+    size_t max_url_size;
+    char *url, *u;
+    URLComponents uc;
+
+    ff_url_decompose(&uc, template, NULL);
+    base_size = URL_COMPONENT_HAVE(uc, scheme) ? 0 : strlen(base);
+
+    max_url_size = base_size +
+                   (template ? strlen(template) : 0) +
+                   $RepresentationID$_size +
+                   (MAX_DIGITS * 3) + 1 /* NUL */;
+
+    if (!(url = av_malloc(max_url_size)))
+        return NULL;
+
+    memcpy(url, base, base_size);
+    u = url + base_size;
+
+    while (template && *template) {
+        char *t;
+
+        if ((t = strchr(template, '$'))) {
+            size_t len;
+            unsigned digits;
+
+            /* Append everything before $. */
+            len = t - template;
+            memcpy(u, template, len);
+            u += len;
+            template = t + 1;
+
+            /* Get length of template name. */
+            len = strcspn(template, "$%");
+
+            /* Parse formatting. It's easy because we have only one
+             * possibility. */
+            digits = 0;
+            (void)av_sscanf(template + len, "%%0%ud$", &digits);
+            if (MAX_DIGITS < digits)
+                digits = MAX_DIGITS;
+
+#define IS(name) (len == sizeof(name) - 1 && !memcmp(template, name, sizeof(name) - 1))
+
+            /* Substitute template argument. */
+            if (IS("RepresentationID")) {
+                memcpy(u, $RepresentationID$, $RepresentationID$_size);
+                u += $RepresentationID$_size;
+            } else if (IS("Time")) {
+                u += sprintf(u, "%0*"PRId64, digits, $Time$);
+            } else if (IS("Bandwidth")) {
+                u += sprintf(u, "%0*"PRIu32, digits, $Bandwidth$);
+            } else if (IS("Number")) {
+                u += sprintf(u, "%0*"PRIu64, digits, $Number$);
+            } else if (IS("")) {
+                *u++ = '$';
+            }
+
+#undef IS
+
+            /* Go over $. */
+            if ((template = strchr(template + len, '$')))
+                ++template;
+        } else {
+            /* Copy remaining. */
+            strcpy(u, template);
+            break;
         }
-        node = xmlNextElementSibling(node);
     }
 
-err:
-    xmlFree(c->adaptionset_lang);
-    c->adaptionset_lang = NULL;
-    return ret;
+    return url;
 }
 
-static int parse_programinformation(AVFormatContext *s, xmlNodePtr node)
+static int64_t dash_subdemuxer_seek(void *opaque, int64_t offset, int whence)
 {
-    xmlChar *val = NULL;
+    DASHRepresentation *rep = opaque;
+    return avio_seek(rep->segments[0].pb, offset, whence);
+}
 
-    node = xmlFirstElementChild(node);
-    while (node) {
-        if (!av_strcasecmp(node->name, "Title")) {
-            val = xmlNodeGetContent(node);
-            if (val) {
-                av_dict_set(&s->metadata, "Title", val, 0);
-            }
-        } else if (!av_strcasecmp(node->name, "Source")) {
-            val = xmlNodeGetContent(node);
-            if (val) {
-                av_dict_set(&s->metadata, "Source", val, 0);
+static av_cold int dash_copy_stream_props(AVStream *slave, AVStream *master)
+{
+    int ret;
+
+    master->event_flags &= ~AVSTREAM_EVENT_FLAG_METADATA_UPDATED;
+    slave->event_flags |= AVSTREAM_EVENT_FLAG_METADATA_UPDATED;
+
+    slave->internal->need_context_update = 1;
+
+    if ((ret = ff_stream_encode_params_copy(slave, master)) < 0)
+        return ret;
+
+    /* Only for probed context (oc->iformat != NULL). */
+    if (master->time_base.den)
+        avpriv_set_pts_info(slave, master->pts_wrap_bits,
+                            master->time_base.num, master->time_base.den);
+
+    return 0;
+}
+
+static av_cold DASHRepresentationPeriod *dash_find_representation_period_at(
+        DASHRepresentation *rep, int64_t timestamp)
+{
+    for (unsigned i = 0; i < rep->nb_periods; ++i) {
+        DASHRepresentationPeriod *period = rep->periods[i];
+        if (period->period->start_ts <= timestamp &&
+                                        timestamp < period->period->end_ts)
+            return period;
+    }
+
+    return NULL;
+}
+
+/**
+ * Update everything to make outside context of the representation look good.
+ *
+ * Must be called after:
+ * - rep->ic->streams changed,
+ * - rep->cur_period changed.
+ */
+static av_cold int dash_subdemuxer_update(DASHRepresentation *rep)
+{
+    int ret;
+    void *p;
+    AVFormatContext *oc = rep->oc;
+    AVFormatContext *ic = rep->ic;
+
+    if (rep->nb_streams < ic->nb_streams) {
+        if (!(p = av_realloc(rep->ostreams, ic->nb_streams * sizeof(*rep->ostreams))))
+            return AVERROR(ENOMEM);
+        rep->ostreams = p;
+    }
+
+    rep->ic->event_flags &= ~AVFMT_EVENT_FLAG_METADATA_UPDATED;
+    rep->oc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
+
+    for (unsigned stream_index = 0;
+         stream_index < ic->nb_streams;
+         stream_index++)
+    {
+        AVStream *ist, *ost;
+        DASHRepresentationPeriod *period;
+        AVDictionary *metadata = NULL;
+
+        ist = ic->streams[stream_index];
+
+        if (stream_index < rep->nb_streams) {
+            ost = rep->ostreams[stream_index];
+        } else {
+            ost = avformat_new_stream(oc, NULL);
+            if (!ost)
+                return AVERROR(ENOMEM);
+
+            rep->ostreams[stream_index] = ost;
+        }
+
+        av_log(oc, AV_LOG_VERBOSE,
+               "Match '%s', stream #%u -> DASH stream #%u\n",
+               rep->id, stream_index, ost->index);
+
+        /* Period specific metadata. */
+        period = rep->cur_period;
+        /* For inactive representations compute where we would be. */
+        if (!period)
+            period = dash_find_representation_period_at(rep, rep->read_ts);
+        if (period) {
+            const DASHParameters *par = &period->par;
+            uint8_t *side_data;
+            size_t side_data_size;
+
+            side_data = av_encryption_init_info_add_side_data(period->as->init_info, &side_data_size);
+            if (!side_data)
+                return AVERROR(ENOMEM);
+
+            ret = av_stream_add_side_data(ist, AV_PKT_DATA_ENCRYPTION_INIT_INFO,
+                                          side_data, side_data_size);
+            if (ret < 0) {
+                av_free(side_data);
+                return ret;
             }
-        } else if (!av_strcasecmp(node->name, "Copyright")) {
-            val = xmlNodeGetContent(node);
-            if (val) {
-                av_dict_set(&s->metadata, "Copyright", val, 0);
+
+            av_dict_set_int(&metadata, "variant_bitrate", period->bandwidth, AV_DICT_MULTIKEY);
+
+            /* AdaptationSet specific metadata. */
+            av_dict_copy(&metadata, period->as->metadata, AV_DICT_MULTIKEY);
+
+            /* Most parameters are only relevant for elementary streams. */
+            if (rep->ic->nb_streams == 1) {
+                AVCodecParameters *codecpar = ist->codecpar;
+
+                /* Set unknown parameters from manifest. */
+
+                if (codecpar->codec_type == AVMEDIA_TYPE_UNKNOWN)
+                    codecpar->codec_type = par->codec_type;
+
+                if (codecpar->codec_id == AV_CODEC_ID_NONE)
+                    codecpar->codec_id = par->codec_id;
+
+                if (!codecpar->sample_rate)
+                    codecpar->sample_rate = par->sample_rate;
+
+                if (!codecpar->channels && !codecpar->channel_layout)
+                    codecpar->channels = par->channels,
+                    codecpar->channel_layout = par->channel_layout;
+
+                if (!codecpar->width && !codecpar->height)
+                    codecpar->width = par->width,
+                    codecpar->height = par->height;
+
+                if (!ist->avg_frame_rate.num)
+                    ist->avg_frame_rate = par->frame_rate;
+                if (!ist->r_frame_rate.num)
+                    ist->r_frame_rate = par->frame_rate;
+
+                if (!codecpar->sample_aspect_ratio.num)
+                    codecpar->sample_aspect_ratio = par->sample_aspect_ratio;
+
+                if (codecpar->field_order == AV_FIELD_UNKNOWN)
+                    codecpar->field_order = par->field_order;
             }
+
+            ist->disposition = par->disposition;
+        }
+
+        /* Representation specific metadata. */
+        av_dict_set(&metadata, "id", rep->id, AV_DICT_MULTIKEY);
+
+        /* RepresentationPeriod (stream) specific metadata. */
+        if ((ret = dash_copy_stream_props(ost, ist)) < 0) {
+            av_dict_free(&metadata);
+            return ret;
         }
-        node = xmlNextElementSibling(node);
-        xmlFree(val);
-        val = NULL;
+
+        av_dict_copy(&ost->metadata, metadata, AV_DICT_MULTIKEY);
+        av_dict_free(&metadata);
+    }
+
+    for (unsigned stream_index = ic->nb_streams;
+         stream_index < rep->nb_streams;
+         stream_index++)
+    {
+        AVStream *ist, *ost;
+
+        /* Dummy format with no streams. */
+        if (!ic->streams)
+            break;
+
+        ist = ic->streams[stream_index];
+        ost = rep->ostreams[stream_index];
+
+        /* Reset codec parameters. */
+        avcodec_parameters_free(&ist->codecpar);
+        ist->codecpar = avcodec_parameters_alloc();
+        if (!ist->codecpar)
+            return AVERROR(ENOMEM);
+
+        if ((ret = dash_copy_stream_props(ost, ist)) < 0)
+            return ret;
     }
+
+    rep->nb_streams = FFMAX(rep->nb_streams, ic->nb_streams);
+
     return 0;
 }
 
-static int parse_manifest(AVFormatContext *s, const char *url, AVIOContext *in)
+static void dash_rotate_urllist(AVFormatContext *s, DASHURLList *urls)
 {
     DASHContext *c = s->priv_data;
-    int ret = 0;
-    int close_in = 0;
-    int64_t filesize = 0;
-    AVBPrint buf;
-    AVDictionary *opts = NULL;
-    xmlDoc *doc = NULL;
-    xmlNodePtr root_element = NULL;
-    xmlNodePtr node = NULL;
-    xmlNodePtr period_node = NULL;
-    xmlNodePtr tmp_node = NULL;
-    xmlNodePtr mpd_baseurl_node = NULL;
-    xmlNodePtr period_baseurl_node = NULL;
-    xmlNodePtr period_segmenttemplate_node = NULL;
-    xmlNodePtr period_segmentlist_node = NULL;
-    xmlNodePtr adaptionset_node = NULL;
-    xmlAttrPtr attr = NULL;
-    char *val  = NULL;
-    uint32_t period_duration_sec = 0;
-    uint32_t period_start_sec = 0;
-
-    if (!in) {
-        close_in = 1;
-
-        av_dict_copy(&opts, c->avio_opts, 0);
-        ret = avio_open2(&in, url, AVIO_FLAG_READ, c->interrupt_callback, &opts);
-        av_dict_free(&opts);
-        if (ret < 0)
-            return ret;
+
+    if (1 < urls->nb) {
+        unsigned const i = 1 + av_lfg_get(&c->rnd) % (urls->nb - 1);
+        char *tmp     = urls->elems[i];
+        urls->elems[i] = urls->elems[0];
+        urls->elems[0] = tmp;
     }
+}
 
-    if (av_opt_get(in, "location", AV_OPT_SEARCH_CHILDREN, (uint8_t**)&c->base_url) < 0)
-        c->base_url = av_strdup(url);
+static int dash_subdemuxer_read(void *opaque, uint8_t *buf, int buf_size)
+{
+    int ret;
+    DASHRepresentation *rep = opaque;
+    AVFormatContext *s = rep->oc;
+    DASHContext *c = s->priv_data;
+    int size;
+    unsigned seg = rep->cur_segment;
+
+open_segment:;
+    do {
+        DASHRepresentationPeriod *period;
+        char *url;
+        const char *base;
+        const char *template;
+        uint64_t $Number$;
+        int64_t $Time$;
+        DASHRange range;
+        AVDictionary *opts;
+#if CONFIG_HTTP_PROTOCOL
+        URLContext *uc;
+#endif
 
-    filesize = avio_size(in);
-    filesize = filesize > 0 ? filesize : DEFAULT_MANIFEST_SIZE;
+        if (rep->segments[seg].pb &&
+            !rep->segments[seg].pb->eof_reached)
+            continue;
 
-    if (filesize > MAX_BPRINT_READ_SIZE) {
-        av_log(s, AV_LOG_ERROR, "Manifest too large: %"PRId64"\n", filesize);
-        return AVERROR_INVALIDDATA;
-    }
+        for (unsigned i = 0; i < rep->nb_periods; ++i) {
+            int64_t period_ts;
+            DASHTimeline *timeline;
 
-    av_bprint_init(&buf, filesize + 1, AV_BPRINT_SIZE_UNLIMITED);
+            period = rep->periods[i];
+            timeline = period->timeline;
 
-    if ((ret = avio_read_to_bprint(in, &buf, MAX_BPRINT_READ_SIZE)) < 0 ||
-        !avio_feof(in) ||
-        (filesize = buf.len) == 0) {
-        av_log(s, AV_LOG_ERROR, "Unable to read to manifest '%s'\n", url);
-        if (ret == 0)
-            ret = AVERROR_INVALIDDATA;
-    } else {
-        LIBXML_TEST_VERSION
+            /* Check if we are inside Period boundaries. */
+            if (!(period->period->start_ts <= rep->read_ts &&
+                                              rep->read_ts < period->period->end_ts))
+                continue;
 
-        doc = xmlReadMemory(buf.str, filesize, c->base_url, NULL, 0);
-        root_element = xmlDocGetRootElement(doc);
-        node = root_element;
+            /* period_ts := read_ts relative to Period start. */
+            period_ts = av_rescale_q_rnd(rep->read_ts - period->period->start_ts,
+                                         AV_TIME_BASE_Q,
+                                         (AVRational){ 1, timeline->timescale },
+                                         AV_ROUND_UP);
+
+            if (timeline->type == TIMELINE_TEMPLATES) {
+                for (unsigned j = 0; j < timeline->u.templates.nb; ++j) {
+                    DASHSegmentTemplate *g = &timeline->u.templates.elems[j];
+                    int64_t end_time = g->repeat < 0 || INT64_MAX / (g->repeat + 1) < g->duration
+                        ? INT64_MAX
+                        : g->start_ts + g->duration * (g->repeat + 1);
+                    end_time = FFMIN(end_time, timeline->duration);
+
+                    if (period_ts < g->start_ts) {
+                        /* Gap detected: Missing segments in timeline. */
+                        period_ts = g->start_ts;
+                        /**
+                         * period_ts := 0
+                         * Timeline@PTO := S
+                         * <S t="S + 1" />
+                         */
+                    }
 
-        if (!node) {
-            ret = AVERROR_INVALIDDATA;
-            av_log(s, AV_LOG_ERROR, "Unable to parse '%s' - missing root node\n", url);
-            goto cleanup;
-        }
+#if 0
+                    av_log(rep->oc, AV_LOG_ERROR, "S@[n=%"PRId64" d*r=%"PRId64"*%"PRId64"]: %"PRId64" <= %"PRId64" <= %"PRId64"?\n",
+                           g->number, g->duration, g->repeat, g->start_ts, period_ts, end_time);
+#endif
+                    if (period_ts < end_time) {
+
+                        /* If period changed push init section first. */
+                        if (rep->cur_period != period) {
+                            if (seg != rep->cur_segment)
+                                goto read_segment;
+
+                            if (!rep->save_init) {
+                                rep->save_init = 1;
+
+                                /* Send out stored part. */
+                                if (0 < period->initbuf_size) {
+                                    memcpy(buf, period->initbuf, period->initbuf_size);
+                                    return period->initbuf_size;
+                                }
+                            }
+
+                            rep->cur_period = period;
+                            ret = dash_subdemuxer_update(rep);
+                            if (ret < 0)
+                                return ret;
+
+                            range = timeline->init.range;
+                            range.start += period->initbuf_size;
+
+                            /* Test whether full segment is stored and thus
+                             * previously has been sent out. */
+                            if (0 < period->initbuf_size &&
+                                (period->initbuf_size < INITBUF_MAX ||
+                                 range.end <= range.start))
+                            {
+                                rep->save_init = 0;
+                                continue;
+                            }
+
+                            $Time$ = 0, $Number$ = 0; /* They should not be used in template URL. */
+                            template = timeline->init.url;
+                        } else {
+                            uint64_t r = (period_ts - g->start_ts) / g->duration;
+                            $Time$ = g->start_ts + g->duration * r;
+                            $Number$ = g->number + r;
+                            template = timeline->u.templates.master.url;
+                            range = timeline->u.templates.master.range;
+
+                            rep->read_ts = av_rescale_q_rnd($Time$ + g->duration,
+                                                            (AVRational){ 1, timeline->timescale },
+                                                            AV_TIME_BASE_Q,
+                                                            AV_ROUND_UP);
+
+                            /* Wait until segment becomes available. */
+                            if (c->is_live) {
+                                int64_t time_shift = rep->read_ts - c->availability_start_time;
+                                if (time_shift < 0) {
+                                    /* Allow suspending thread only when it is really neccessary, i.e. we have no other segments to serve. */
+                                    if (seg == rep->cur_segment)
+                                        av_usleep(-time_shift);
+                                    else
+                                        goto read_segment;
+                                }
+                            }
+                        }
+                        base = period->base->elems[0];
+
+                        goto found;
+                    }
+                }
+            } else if (timeline->type == TIMELINE_SEGMENTS) {
+                DASHSegment *g;
+
+                if (rep->cur_period != period) {
+                    if (seg != rep->cur_segment)
+                        goto read_segment;
+
+                    rep->cur_period = period;
+                    ret = dash_subdemuxer_update(rep);
+                    if (ret < 0)
+                        return ret;
+
+                    g = &timeline->init;
+                } else if (0 < timeline->u.segments.nb) {
+                    int64_t segment_ts = timeline->duration / timeline->u.segments.nb;
+                    g = &timeline->u.segments.elems[period_ts / segment_ts];
+                } else {
+                    /* One segment timeline. */
+                    continue;
+                }
 
-        if (node->type != XML_ELEMENT_NODE ||
-            av_strcasecmp(node->name, "MPD")) {
-            ret = AVERROR_INVALIDDATA;
-            av_log(s, AV_LOG_ERROR, "Unable to parse '%s' - wrong root node name[%s] type[%d]\n", url, node->name, (int)node->type);
-            goto cleanup;
-        }
+                base = period->base->elems[0];
+                template = g->url; /* HACK: URL is not template. */
+                range = g->range;
 
-        val = xmlGetProp(node, "type");
-        if (!val) {
-            av_log(s, AV_LOG_ERROR, "Unable to parse '%s' - missing type attrib\n", url);
-            ret = AVERROR_INVALIDDATA;
-            goto cleanup;
-        }
-        if (!av_strcasecmp(val, "dynamic"))
-            c->is_live = 1;
-        xmlFree(val);
-
-        attr = node->properties;
-        while (attr) {
-            val = xmlGetProp(node, attr->name);
-
-            if (!av_strcasecmp(attr->name, "availabilityStartTime")) {
-                c->availability_start_time = get_utc_date_time_insec(s, val);
-                av_log(s, AV_LOG_TRACE, "c->availability_start_time = [%"PRId64"]\n", c->availability_start_time);
-            } else if (!av_strcasecmp(attr->name, "availabilityEndTime")) {
-                c->availability_end_time = get_utc_date_time_insec(s, val);
-                av_log(s, AV_LOG_TRACE, "c->availability_end_time = [%"PRId64"]\n", c->availability_end_time);
-            } else if (!av_strcasecmp(attr->name, "publishTime")) {
-                c->publish_time = get_utc_date_time_insec(s, val);
-                av_log(s, AV_LOG_TRACE, "c->publish_time = [%"PRId64"]\n", c->publish_time);
-            } else if (!av_strcasecmp(attr->name, "minimumUpdatePeriod")) {
-                c->minimum_update_period = get_duration_insec(s, val);
-                av_log(s, AV_LOG_TRACE, "c->minimum_update_period = [%"PRId64"]\n", c->minimum_update_period);
-            } else if (!av_strcasecmp(attr->name, "timeShiftBufferDepth")) {
-                c->time_shift_buffer_depth = get_duration_insec(s, val);
-                av_log(s, AV_LOG_TRACE, "c->time_shift_buffer_depth = [%"PRId64"]\n", c->time_shift_buffer_depth);
-            } else if (!av_strcasecmp(attr->name, "minBufferTime")) {
-                c->min_buffer_time = get_duration_insec(s, val);
-                av_log(s, AV_LOG_TRACE, "c->min_buffer_time = [%"PRId64"]\n", c->min_buffer_time);
-            } else if (!av_strcasecmp(attr->name, "suggestedPresentationDelay")) {
-                c->suggested_presentation_delay = get_duration_insec(s, val);
-                av_log(s, AV_LOG_TRACE, "c->suggested_presentation_delay = [%"PRId64"]\n", c->suggested_presentation_delay);
-            } else if (!av_strcasecmp(attr->name, "mediaPresentationDuration")) {
-                c->media_presentation_duration = get_duration_insec(s, val);
-                av_log(s, AV_LOG_TRACE, "c->media_presentation_duration = [%"PRId64"]\n", c->media_presentation_duration);
+                goto found;
+            } else {
+                abort();
             }
-            attr = attr->next;
-            xmlFree(val);
+
+            /* Gap detected: No more segments till end of the period. Jump to
+             * the end of the period. */
+            rep->read_ts = period->period->end_ts;
+
+            /* Periods may be out-of-order so start searching next one from the beginning. */
+            i = 0;
         }
 
-        tmp_node = find_child_node_by_name(node, "BaseURL");
-        if (tmp_node) {
-            mpd_baseurl_node = xmlCopyNode(tmp_node,1);
+        if (seg == rep->cur_segment)
+            return AVERROR_EOF;
+        else
+            goto read_segment;
+
+    found:
+        if (template) {
+            url = dash_make_url(base, template, rep->id, $Number$, $Time$, period->bandwidth);
+            if (!url)
+                return AVERROR(ENOMEM);
         } else {
-            mpd_baseurl_node = xmlNewNode(NULL, "BaseURL");
+            url = (char *)base;
         }
 
-        // at now we can handle only one period, with the longest duration
-        node = xmlFirstElementChild(node);
-        while (node) {
-            if (!av_strcasecmp(node->name, "Period")) {
-                period_duration_sec = 0;
-                period_start_sec = 0;
-                attr = node->properties;
-                while (attr) {
-                    val = xmlGetProp(node, attr->name);
-                    if (!av_strcasecmp(attr->name, "duration")) {
-                        period_duration_sec = get_duration_insec(s, val);
-                    } else if (!av_strcasecmp(attr->name, "start")) {
-                        period_start_sec    = get_duration_insec(s, val);
+        opts = NULL;
+
+        if (0 < range.start)
+            av_dict_set_int(&opts, "offset", range.start, 0);
+
+        if (range.end < INT64_MAX)
+            av_dict_set_int(&opts, "end_offset", range.end, 0);
+
+        av_dict_set(&opts, "multiple_requests", "1", 0);
+        av_dict_copy(&opts, c->protocol_opts, 0);
+
+#if CONFIG_HTTP_PROTOCOL
+        if (!(uc = ffio_geturlcontext(rep->segments[seg].pb)) ||
+             (rep->segments[seg].pb->eof_reached = 0,
+              rep->segments[seg].pb->pos = 0,
+              (ret = ff_http_do_new_request2(uc, url, &opts)) < 0))
+#endif
+        {
+            ff_format_io_close(s, &rep->segments[seg].pb);
+            ret = s->io_open(s, &rep->segments[seg].pb, url, AVIO_FLAG_READ, &opts);
+        }
+
+        if (template)
+            av_free(url);
+        av_dict_free(&opts);
+
+        if (ret < 0) {
+        fail_segment:
+            if (seg == rep->cur_segment) {
+                /* We know that we have not reached the end. */
+                if (rep->read_ts < period->period->end_ts) {
+                    if (0) {
+                        /* TODO: Implement some failure resistance in case of
+                         * specific HTTP response codes. */
+                        goto open_segment;
+                    } else if (!c->is_live && (ret == AVERROR(ETIMEDOUT) || ret == AVERROR(EIO))) {
+                        /* Allow dropping some segments only for live streams. */
+                        goto open_segment;
                     }
-                    attr = attr->next;
-                    xmlFree(val);
-                }
-                if ((period_duration_sec) >= (c->period_duration)) {
-                    period_node = node;
-                    c->period_duration = period_duration_sec;
-                    c->period_start = period_start_sec;
-                    if (c->period_start > 0)
-                        c->media_presentation_duration = c->period_duration;
                 }
-            } else if (!av_strcasecmp(node->name, "ProgramInformation")) {
-                parse_programinformation(s, node);
+
+                return ret;
+            } else {
+                goto read_segment;
             }
-            node = xmlNextElementSibling(node);
-        }
-        if (!period_node) {
-            av_log(s, AV_LOG_ERROR, "Unable to parse '%s' - missing Period node\n", url);
-            ret = AVERROR_INVALIDDATA;
-            goto cleanup;
         }
 
-        adaptionset_node = xmlFirstElementChild(period_node);
-        while (adaptionset_node) {
-            if (!av_strcasecmp(adaptionset_node->name, "BaseURL")) {
-                period_baseurl_node = adaptionset_node;
-            } else if (!av_strcasecmp(adaptionset_node->name, "SegmentTemplate")) {
-                period_segmenttemplate_node = adaptionset_node;
-            } else if (!av_strcasecmp(adaptionset_node->name, "SegmentList")) {
-                period_segmentlist_node = adaptionset_node;
-            } else if (!av_strcasecmp(adaptionset_node->name, "AdaptationSet")) {
-                parse_manifest_adaptationset(s, url, adaptionset_node, mpd_baseurl_node, period_baseurl_node, period_segmenttemplate_node, period_segmentlist_node);
+        if (0 < range.start &&
+            avio_seek(s->pb, range.start, SEEK_SET) != range.start)
+        {
+            ret = AVERROR(EIO);
+            goto fail_segment;
+        }
+
+        rep->segments[seg].segment_size = range.end - range.start;
+    } while (rep->cur_segment != (seg = (seg + 1) % c->nb_connections) &&
+             /* Use only a single IO context on startup. */
+             rep->ic->iformat);
+
+read_segment:;
+    /* Only the current segment can be read. */
+    size = FFMIN(buf_size, (int)FFMIN(rep->segments[rep->cur_segment].segment_size, (uint64_t)INT_MAX));
+    av_assert1(0 < size);
+    ret = avio_read_partial(rep->segments[rep->cur_segment].pb, buf, size);
+    if (0 < ret) {
+        rep->segments[rep->cur_segment].segment_size -= ret;
+        if (rep->save_init) {
+            uint8_t *p;
+            /* How much bytes can we store? */
+            int append_size = FFMIN(rep->cur_period->initbuf_size + ret, INITBUF_MAX) -
+                              rep->cur_period->initbuf_size;
+
+            if ((p = av_realloc(rep->cur_period->initbuf, rep->cur_period->initbuf_size + append_size))) {
+                memcpy((rep->cur_period->initbuf = p) + rep->cur_period->initbuf_size, buf, append_size);
+                rep->cur_period->initbuf_size += append_size;
+            } else {
+                /* Do not save anything furthermore otherwise cached init data
+                 * would may be restored with a missing intermediate chunk. */
+                rep->save_init = 0;
+                /* Heck. Reset stored stuff. We can only handle correctly
+                 * received init buffer. */
+                rep->cur_period->initbuf_size = 0;
             }
-            adaptionset_node = xmlNextElementSibling(adaptionset_node);
         }
-cleanup:
-        /*free the document */
-        xmlFreeDoc(doc);
-        xmlCleanupParser();
-        xmlFreeNode(mpd_baseurl_node);
+        return ret;
+    } else if (ret == AVERROR_EOF) {
+        /* Go to next segment. */
+        rep->cur_segment = (rep->cur_segment + 1) % c->nb_connections;
+        rep->save_init = 0;
+    } else if (ret == AVERROR(ETIMEDOUT)) {
+        dash_rotate_urllist(s, rep->cur_period->base);
+    } else if (ret == 0) {
+        if (s->flags & AVFMT_FLAG_NONBLOCK) {
+            return AVERROR(EAGAIN);
+        } else {
+            av_usleep(150 * MILLISEC_PER_SEC);
+            goto read_segment;
+        }
+    } else {
+        return ret;
+    }
+
+    goto open_segment;
+}
+
+static av_cold int dash_subdemuxer_block_io_open(AVFormatContext *s, AVIOContext **pb, const char *url,
+                                                 int flags, AVDictionary **opts)
+{
+    DASHContext *c = s->priv_data;
+    av_log(s, AV_LOG_ERROR,
+           "Opening external resource '%s' from DASH segment '%s' has been blocked for security reasons",
+           url, c->location);
+    av_log(s, AV_LOG_VERBOSE,
+           "To avoid this security guard open MPD manifest using 'file' protocol");
+    return AVERROR(EPERM);
+}
+
+static av_cold int dash_subdemuxer_alloc(DASHRepresentation *rep)
+{
+    int ret = 0;
+    AVFormatContext *s = rep->oc;
+    DASHContext *c = s->priv_data;
+    uint8_t *buf;
+    int buf_size;
+
+    dash_subdemuxer_close(rep);
+
+    /* Allocate space that is enough for the theoretically largest segment. */
+    buf_size = rep->periods[0]->bandwidth * c->max_segment_duration / AV_TIME_BASE;
+    /* When maximum is not enough. */
+    buf_size += buf_size / 16 /* +~5% */;
+    buf_size = FFMIN(FFMAX(buf_size, 4 * 1024), 256 * 1024);
+
+    if (!(buf = av_malloc(buf_size + AV_INPUT_BUFFER_PADDING_SIZE))) {
+        ret = AVERROR(ENOMEM);
+        goto out;
     }
 
-    av_bprint_finalize(&buf, NULL);
-    if (close_in) {
-        avio_close(in);
+    if ((ret = ffio_init_context(&rep->ic_pb, buf, buf_size, 0, rep,
+                                 dash_subdemuxer_read, NULL, dash_subdemuxer_seek) < 0))
+    {
+        /* Note: We purposely do not free I/O buffer since documentation says
+         * nothing about it. We presume inputs are freed on error. Just like in
+         * case av_dict_set() and avformat_alloc_context()... */
+        goto out;
+    }
+    rep->ic_pb.seekable = 0;
+
+    /* Padding bytes must be zeroed out. */
+    memset(buf + buf_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
+
+    if (!(rep->ic = avformat_alloc_context())) {
+        ret = AVERROR(ENOMEM);
+        goto out;
     }
+
+    rep->ic->pb = &rep->ic_pb;
+    rep->ic->interrupt_callback = s->interrupt_callback;
+
+    rep->ic->probesize = 0 < s->probesize
+        ? s->probesize
+        : 4 * 1024;
+    rep->ic->max_analyze_duration = 0 < s->max_analyze_duration
+        ? s->max_analyze_duration
+        : 4 * AV_TIME_BASE;
+
+    /* We supply everything for the demuxer so normall it should not need to
+     * open anything. Apply this restriction unless we use "file" protocol. */
+    if (strcmp(avio_find_protocol_name(s->url), "file"))
+        rep->ic->io_open = dash_subdemuxer_block_io_open;
+
+    if ((ret = ff_copy_whiteblacklists(rep->ic, s)) < 0)
+        goto out;
+
+out:
+    if (ret < 0)
+        dash_subdemuxer_close(rep);
     return ret;
 }
 
-static int64_t calc_cur_seg_no(AVFormatContext *s, struct representation *pls)
+/**
+ * Open the real context.
+ */
+static av_cold int dash_subdemuxer_open(DASHRepresentation *rep)
 {
-    DASHContext *c = s->priv_data;
-    int64_t num = 0;
-    int64_t start_time_offset = 0;
+    int ret = 0;
+    AVFormatContext *s = rep->oc;
+    AVInputFormat *iformat = NULL;
 
-    if (c->is_live) {
-        if (pls->n_fragments) {
-            av_log(s, AV_LOG_TRACE, "in n_fragments mode\n");
-            num = pls->first_seq_no;
-        } else if (pls->n_timelines) {
-            av_log(s, AV_LOG_TRACE, "in n_timelines mode\n");
-            start_time_offset = get_segment_start_time_based_on_timeline(pls, 0xFFFFFFFF) - 60 * pls->fragment_timescale; // 60 seconds before end
-            num = calc_next_seg_no_from_timelines(pls, start_time_offset);
-            if (num == -1)
-                num = pls->first_seq_no;
-            else
-                num += pls->first_seq_no;
-        } else if (pls->fragment_duration){
-            av_log(s, AV_LOG_TRACE, "in fragment_duration mode fragment_timescale = %"PRId64", presentation_timeoffset = %"PRId64"\n", pls->fragment_timescale, pls->presentation_timeoffset);
-            if (pls->presentation_timeoffset) {
-                num = pls->first_seq_no + (((get_current_time_in_sec() - c->availability_start_time) * pls->fragment_timescale)-pls->presentation_timeoffset) / pls->fragment_duration - c->min_buffer_time;
-            } else if (c->publish_time > 0 && !c->availability_start_time) {
-                if (c->min_buffer_time) {
-                    num = pls->first_seq_no + (((c->publish_time + pls->fragment_duration) - c->suggested_presentation_delay) * pls->fragment_timescale) / pls->fragment_duration - c->min_buffer_time;
-                } else {
-                    num = pls->first_seq_no + (((c->publish_time - c->time_shift_buffer_depth + pls->fragment_duration) - c->suggested_presentation_delay) * pls->fragment_timescale) / pls->fragment_duration;
-                }
-            } else {
-                num = pls->first_seq_no + (((get_current_time_in_sec() - c->availability_start_time) - c->suggested_presentation_delay) * pls->fragment_timescale) / pls->fragment_duration;
-            }
-        }
-    } else {
-        num = pls->first_seq_no;
+    av_log(s, AV_LOG_DEBUG, "Opening representation '%s'\n", rep->id);
+
+    if ((ret = dash_subdemuxer_alloc(rep)) < 0)
+        goto out;
+
+    if ((ret = av_probe_input_buffer(&rep->ic_pb, &iformat, NULL, NULL, 0, 0)) < 0) {
+        av_log(s, AV_LOG_ERROR, "Probe failed for representation '%s'\n", rep->id);
+        goto out;
     }
-    return num;
+
+    if ((ret = avformat_open_input(&rep->ic, NULL, iformat, NULL)) < 0)
+        goto out;
+
+    /* Finding stream information may need some essential information, like
+     * encryption init info so stream metadata must be updated before. */
+    if ((ret = dash_subdemuxer_update(rep)))
+        goto out;
+
+    if ((ret = avformat_find_stream_info(rep->ic, NULL)) < 0)
+        goto out;
+
+    /* Though new streams may have been created we do not care about them now.
+     * If this is the case or stream information otherwise changed it will get
+     * updated after reading frames. */
+
+out:
+    if (ret < 0)
+        dash_subdemuxer_close(rep);
+    return ret;
 }
 
-static int64_t calc_min_seg_no(AVFormatContext *s, struct representation *pls)
+static av_cold int dash_subdemuxer_init(DASHRepresentation *rep)
 {
+    int ret;
+    AVFormatContext *s = rep->oc;
     DASHContext *c = s->priv_data;
-    int64_t num = 0;
 
-    if (c->is_live && pls->fragment_duration) {
-        av_log(s, AV_LOG_TRACE, "in live mode\n");
-        num = pls->first_seq_no + (((get_current_time_in_sec() - c->availability_start_time) - c->time_shift_buffer_depth) * pls->fragment_timescale) / pls->fragment_duration;
-    } else {
-        num = pls->first_seq_no;
+    if (c->is_live)
+        rep->read_ts = av_gettime() - FFMIN(10, c->time_shift_buffer_depth) * MICROSEC_PER_SEC;
+    else
+        rep->read_ts = c->start_ts;
+
+    /* Create an inital stream for this representation though we do not what is
+     * really inside. We expect it to be an elementary stream however it do not
+     * have to be always true. In such cases the new streams will appear in
+     * dash_subdemuxer_open(). */
+    if (!avformat_new_stream(rep->ic, NULL)) {
+        ret = AVERROR(ENOMEM);
+        goto out;
     }
-    return num;
+
+    if ((ret = dash_subdemuxer_update(rep)) < 0)
+        goto out;
+
+out:
+    if (ret < 0)
+        dash_subdemuxer_close(rep);
+    return ret;
+}
+
+static void *av_push_array(void *plist, unsigned elem_size)
+{
+    void *p;
+    unsigned *nmemb = (unsigned *)((void **)plist + 1);
+
+    if (!(p = av_realloc(*(void **)plist, (*nmemb + 1) * sizeof(void *))))
+        return NULL;
+    *(void **)plist = p;
+
+    return ((*(void ***)plist)[(*nmemb)++] = av_mallocz(elem_size));
 }
 
-static int64_t calc_max_seg_no(struct representation *pls, DASHContext *c)
+static av_cold void *dash_find_by_id(AVFormatContext *s, void *list, unsigned nmemb, const char *id)
 {
-    int64_t num = 0;
+    if (!id)
+        return NULL;
 
-    if (pls->n_fragments) {
-        num = pls->first_seq_no + pls->n_fragments - 1;
-    } else if (pls->n_timelines) {
-        int i = 0;
-        num = pls->first_seq_no + pls->n_timelines - 1;
-        for (i = 0; i < pls->n_timelines; i++) {
-            if (pls->timelines[i]->repeat == -1) {
-                int length_of_each_segment = pls->timelines[i]->duration / pls->fragment_timescale;
-                num =  c->period_duration / length_of_each_segment;
-            } else {
-                num += pls->timelines[i]->repeat;
-            }
-        }
-    } else if (c->is_live && pls->fragment_duration) {
-        num = pls->first_seq_no + (((get_current_time_in_sec() - c->availability_start_time)) * pls->fragment_timescale)  / pls->fragment_duration;
-    } else if (pls->fragment_duration) {
-        num = pls->first_seq_no + (c->media_presentation_duration * pls->fragment_timescale) / pls->fragment_duration;
+    for (unsigned i = 0; i < nmemb; ++i) {
+        void *elem = ((void **)list)[i];
+        xmlChar *elem_id = *(xmlChar **)elem;
+        if (elem_id && !strcmp(elem_id, id))
+            return elem;
     }
 
-    return num;
+    return NULL;
 }
 
-static void move_timelines(struct representation *rep_src, struct representation *rep_dest, DASHContext *c)
+static av_cold int dash_push_id_node(AVFormatContext *s, void *elem, void *plist, unsigned elem_size, xmlNodePtr node)
 {
-    if (rep_dest && rep_src ) {
-        free_timelines_list(rep_dest);
-        rep_dest->timelines    = rep_src->timelines;
-        rep_dest->n_timelines  = rep_src->n_timelines;
-        rep_dest->first_seq_no = rep_src->first_seq_no;
-        rep_dest->last_seq_no = calc_max_seg_no(rep_dest, c);
-        rep_src->timelines = NULL;
-        rep_src->n_timelines = 0;
-        rep_dest->cur_seq_no = rep_src->cur_seq_no;
+    int ret;
+    xmlChar *id = xmlGetNoNsProp(node, "id");
+    unsigned *nmemb = (unsigned *)((void **)plist + 1);
+
+    if ((*(void **)elem = dash_find_by_id(s, *(void ***)plist, *nmemb, id))) {
+        ret = 1;
+    } else if ((*(void **)elem = av_push_array(plist, elem_size))) {
+        *(xmlChar **)(*(void **)elem) = id;
+        id = NULL;
+        ret = 0;
+    } else {
+        ret = AVERROR(ENOMEM);
     }
+
+    xml_free(id);
+    return ret;
 }
 
-static void move_segments(struct representation *rep_src, struct representation *rep_dest, DASHContext *c)
+static int dash_parse_representation(AVFormatContext *s,
+                                     DASHPeriod *period,
+                                     DASHAdaptationSet *as,
+                                     DASHURLList *base_urls,
+                                     DASHTimeline *inherited_timeline,
+                                     const DASHParameters *inherited_par,
+                                     xmlNodePtr node)
 {
-    if (rep_dest && rep_src ) {
-        free_fragment_list(rep_dest);
-        if (rep_src->start_number > (rep_dest->start_number + rep_dest->n_fragments))
-            rep_dest->cur_seq_no = 0;
-        else
-            rep_dest->cur_seq_no += rep_src->start_number - rep_dest->start_number;
-        rep_dest->fragments    = rep_src->fragments;
-        rep_dest->n_fragments  = rep_src->n_fragments;
-        rep_dest->parent  = rep_src->parent;
-        rep_dest->last_seq_no = calc_max_seg_no(rep_dest, c);
-        rep_src->fragments = NULL;
-        rep_src->n_fragments = 0;
+    int ret = 0;
+    DASHContext *c = s->priv_data;
+    DASHURLList *urls = dash_ref_urllist(base_urls);
+    DASHRepresentation *rep;
+    DASHRepresentationPeriod *rep_period;
+    DASHTimeline *timeline = NULL;
+    int64_t availability_time_offset = 0;
+
+    if ((ret = dash_push_id_node(s, &rep, &c->reps, offsetof(DASHRepresentation, segments[c->nb_connections]), node)) < 0)
+        goto out;
+    else if (!ret) {
+        rep->oc = s;
     }
-}
 
+    if (!(rep_period = av_push_array(&rep->periods, sizeof(DASHRepresentationPeriod)))) {
+        ret = AVERROR(ENOMEM);
+        goto out;
+    }
+
+    rep_period->period = period;
+    rep_period->par = *inherited_par;
+
+    xml_for_each_attr {
+        if (!strcmp(attr->name, "availabilityTimeOffset"))
+            (void)av_sscanf(value, "%"SCNd64, &availability_time_offset);
+        else if (!strcmp(attr->name, "bandwidth"))
+            (void)av_sscanf(value, "%"SCNu32, &rep_period->bandwidth);
+        else if (!dash_parse_parameters(s, &rep_period->par, attr, value))
+            /* Already done. */;
+        else if (!strcmp(attr->name, "startWithSAP") && !strcmp(value, "1"))
+            /* Just check. */;
+        else if (strcmp(attr->name, "id"))
+            dash_log_unknown_attr(s, attr, value);
+    }
+
+    xml_for_each_child {
+        if (!strcmp(child->name, "BaseURL"))
+            ret = dash_parse_baseurl(s, &urls, child);
+        else if (!strcmp(child->name, "SegmentTemplate"))
+            ret = dash_parse_segmenttemplate(s, period, &timeline, child);
+        else if (!strcmp(child->name, "SegmentList"))
+            ret = dash_parse_segmentlist(s, period, &timeline, child);
+        else if (!strcmp(child->name, "SegmentBase"))
+            ret = dash_parse_segmentbase(s, period, &timeline, child);
+        else if (!strcmp(child->name, "AudioChannelConfiguration"))
+            ret = dash_parse_audiochannelconfiguration(s, &rep_period->par, child);
+        else if (!strcmp(child->name, "UTCTiming"))
+            ret = dash_parse_utctiming(s, child);
+        else
+            dash_log_unknown_child(s, child);
 
-static int refresh_manifest(AVFormatContext *s)
-{
-    int ret = 0, i;
-    DASHContext *c = s->priv_data;
-    // save current context
-    int n_videos = c->n_videos;
-    struct representation **videos = c->videos;
-    int n_audios = c->n_audios;
-    struct representation **audios = c->audios;
-    int n_subtitles = c->n_subtitles;
-    struct representation **subtitles = c->subtitles;
-    char *base_url = c->base_url;
-
-    c->base_url = NULL;
-    c->n_videos = 0;
-    c->videos = NULL;
-    c->n_audios = 0;
-    c->audios = NULL;
-    c->n_subtitles = 0;
-    c->subtitles = NULL;
-    ret = parse_manifest(s, s->url, NULL);
-    if (ret)
-        goto finish;
-
-    if (c->n_videos != n_videos) {
-        av_log(c, AV_LOG_ERROR,
-               "new manifest has mismatched no. of video representations, %d -> %d\n",
-               n_videos, c->n_videos);
-        return AVERROR_INVALIDDATA;
+        if (ret < 0)
+            goto out;
     }
-    if (c->n_audios != n_audios) {
-        av_log(c, AV_LOG_ERROR,
-               "new manifest has mismatched no. of audio representations, %d -> %d\n",
-               n_audios, c->n_audios);
-        return AVERROR_INVALIDDATA;
+
+    rep_period->as = as;
+    if (!timeline && inherited_timeline)
+        timeline = dash_ref_timeline(inherited_timeline);
+    /* Default timeline with one big segment. URL is obtained from BaseURLs. */
+    if (!timeline && (timeline = av_mallocz(sizeof(DASHTimeline)))) {
+        dash_ref_timeline(timeline);
+        timeline->type = TIMELINE_SEGMENTS;
+        timeline->duration = INT64_MAX;
+        timeline->init.range = DASH_RANGE_INITIALIZER;
     }
-    if (c->n_subtitles != n_subtitles) {
-        av_log(c, AV_LOG_ERROR,
-               "new manifest has mismatched no. of subtitles representations, %d -> %d\n",
-               n_subtitles, c->n_subtitles);
-        return AVERROR_INVALIDDATA;
+    if (!timeline) {
+        ret = AVERROR(ENOMEM);
+        goto out;
     }
+    rep_period->base = dash_ref_urllist(urls);
+    rep_period->timeline = dash_ref_timeline(timeline);
 
-    for (i = 0; i < n_videos; i++) {
-        struct representation *cur_video = videos[i];
-        struct representation *ccur_video = c->videos[i];
-        if (cur_video->timelines) {
-            // calc current time
-            int64_t currentTime = get_segment_start_time_based_on_timeline(cur_video, cur_video->cur_seq_no) / cur_video->fragment_timescale;
-            // update segments
-            ccur_video->cur_seq_no = calc_next_seg_no_from_timelines(ccur_video, currentTime * cur_video->fragment_timescale - 1);
-            if (ccur_video->cur_seq_no >= 0) {
-                move_timelines(ccur_video, cur_video, c);
-            }
-        }
-        if (cur_video->fragments) {
-            move_segments(ccur_video, cur_video, c);
-        }
-    }
-    for (i = 0; i < n_audios; i++) {
-        struct representation *cur_audio = audios[i];
-        struct representation *ccur_audio = c->audios[i];
-        if (cur_audio->timelines) {
-            // calc current time
-            int64_t currentTime = get_segment_start_time_based_on_timeline(cur_audio, cur_audio->cur_seq_no) / cur_audio->fragment_timescale;
-            // update segments
-            ccur_audio->cur_seq_no = calc_next_seg_no_from_timelines(ccur_audio, currentTime * cur_audio->fragment_timescale - 1);
-            if (ccur_audio->cur_seq_no >= 0) {
-                move_timelines(ccur_audio, cur_audio, c);
-            }
-        }
-        if (cur_audio->fragments) {
-            move_segments(ccur_audio, cur_audio, c);
-        }
+    if ((ret = dash_subdemuxer_alloc(rep)) < 0 ||
+        (ret = dash_subdemuxer_init(rep)) < 0)
+    {
+        av_log(s, AV_LOG_DEBUG, "Failed to initalize subdemuxer for representation '%s': %s\n",
+               rep->id, av_err2str(ret));
+        goto out;
     }
 
-finish:
-    // restore context
-    if (c->base_url)
-        av_free(base_url);
-    else
-        c->base_url  = base_url;
-
-    if (c->subtitles)
-        free_subtitle_list(c);
-    if (c->audios)
-        free_audio_list(c);
-    if (c->videos)
-        free_video_list(c);
-
-    c->n_subtitles = n_subtitles;
-    c->subtitles = subtitles;
-    c->n_audios = n_audios;
-    c->audios = audios;
-    c->n_videos = n_videos;
-    c->videos = videos;
+out:
+    dash_unref_timeline(timeline);
+    dash_unref_urllist(urls);
     return ret;
 }
 
-static struct fragment *get_current_fragment(struct representation *pls)
+static av_cold int dash_parse_label(AVFormatContext *s,
+                                    DASHAdaptationSet *as,
+                                    xmlNodePtr node)
 {
-    int64_t min_seq_no = 0;
-    int64_t max_seq_no = 0;
-    struct fragment *seg = NULL;
-    struct fragment *seg_ptr = NULL;
-    DASHContext *c = pls->parent->priv_data;
+    xmlChar *lang = NULL;
+    xmlChar *value;
 
-    while (( !ff_check_interrupt(c->interrupt_callback)&& pls->n_fragments > 0)) {
-        if (pls->cur_seq_no < pls->n_fragments) {
-            seg_ptr = pls->fragments[pls->cur_seq_no];
-            seg = av_mallocz(sizeof(struct fragment));
-            if (!seg) {
-                return NULL;
-            }
-            seg->url = av_strdup(seg_ptr->url);
-            if (!seg->url) {
-                av_free(seg);
-                return NULL;
-            }
-            seg->size = seg_ptr->size;
-            seg->url_offset = seg_ptr->url_offset;
-            return seg;
-        } else if (c->is_live) {
-            refresh_manifest(pls->parent);
-        } else {
-            break;
-        }
+    xml_for_each_attr {
+        if (!strcmp(attr->name, "lang")) {
+            lang = value;
+            value = NULL;
+        } else
+            dash_log_unknown_attr(s, attr, value);
     }
-    if (c->is_live) {
-        min_seq_no = calc_min_seg_no(pls->parent, pls);
-        max_seq_no = calc_max_seg_no(pls, c);
 
-        if (pls->timelines || pls->fragments) {
-            refresh_manifest(pls->parent);
-        }
-        if (pls->cur_seq_no <= min_seq_no) {
-            av_log(pls->parent, AV_LOG_VERBOSE, "old fragment: cur[%"PRId64"] min[%"PRId64"] max[%"PRId64"]\n", (int64_t)pls->cur_seq_no, min_seq_no, max_seq_no);
-            pls->cur_seq_no = calc_cur_seg_no(pls->parent, pls);
-        } else if (pls->cur_seq_no > max_seq_no) {
-            av_log(pls->parent, AV_LOG_VERBOSE, "new fragment: min[%"PRId64"] max[%"PRId64"]\n", min_seq_no, max_seq_no);
-        }
-        seg = av_mallocz(sizeof(struct fragment));
-        if (!seg) {
-            return NULL;
-        }
-    } else if (pls->cur_seq_no <= pls->last_seq_no) {
-        seg = av_mallocz(sizeof(struct fragment));
-        if (!seg) {
-            return NULL;
-        }
-    }
-    if (seg) {
-        char *tmpfilename;
-        if (!pls->url_template) {
-            av_log(pls->parent, AV_LOG_ERROR, "Cannot get fragment, missing template URL\n");
-            av_free(seg);
-            return NULL;
-        }
-        tmpfilename = av_mallocz(c->max_url_size);
-        if (!tmpfilename) {
-            av_free(seg);
-            return NULL;
-        }
-        ff_dash_fill_tmpl_params(tmpfilename, c->max_url_size, pls->url_template, 0, pls->cur_seq_no, 0, get_segment_start_time_based_on_timeline(pls, pls->cur_seq_no));
-        seg->url = av_strireplace(pls->url_template, pls->url_template, tmpfilename);
-        if (!seg->url) {
-            av_log(pls->parent, AV_LOG_WARNING, "Unable to resolve template url '%s', try to use origin template\n", pls->url_template);
-            seg->url = av_strdup(pls->url_template);
-            if (!seg->url) {
-                av_log(pls->parent, AV_LOG_ERROR, "Cannot resolve template url '%s'\n", pls->url_template);
-                av_free(tmpfilename);
-                av_free(seg);
-                return NULL;
-            }
-        }
-        av_free(tmpfilename);
-        seg->size = -1;
+    if ((value = xmlNodeGetContent(node)) && *value) {
+        char key_lang[100];
+        if (lang)
+            sprintf(key_lang, "label-%s", lang);
+        av_dict_set(&s->metadata, lang ? key_lang : "label", value, 0);
     }
 
-    return seg;
+    xml_free(value);
+    xml_free(lang);
+    return 0;
 }
 
-static int read_from_url(struct representation *pls, struct fragment *seg,
-                         uint8_t *buf, int buf_size)
+static av_cold int dash_parse_adaptationset(AVFormatContext *s,
+                                            DASHPeriod *period,
+                                            DASHURLList *base_urls,
+                                            DASHTimeline *inherited_timeline,
+                                            const DASHParameters *inherited_par,
+                                            xmlNodePtr node)
 {
-    int ret;
-
-    /* limit read if the fragment was only a part of a file */
-    if (seg->size >= 0)
-        buf_size = FFMIN(buf_size, pls->cur_seg_size - pls->cur_seg_offset);
+    int ret = 0;
+    DASHContext *c = s->priv_data;
+    DASHContentProtection cp = DASH_CONTENTPROTECTION_INITIALIZER;
+    DASHURLList *urls = dash_ref_urllist(base_urls);
+    DASHAdaptationSet *as;
+    DASHTimeline *timeline = NULL;
+    DASHParameters par = *inherited_par;
+
+    if ((ret = dash_push_id_node(s, &as, &c->ass, sizeof(DASHAdaptationSet), node)) < 0)
+        goto out;
+
+    xml_for_each_attr {
+        if (!strcmp(attr->name, "lang"))
+            av_dict_set(&as->metadata, "language", value, 0);
+        else if (!strcmp(attr->name, "selectionPriority"))
+            av_dict_set(&as->metadata, "priority", value, 0);
+        else if (!strcmp(attr->name, "group"))
+            av_dict_set(&as->metadata, "group", value, 0);
+        else if (!dash_parse_parameters(s, &par, attr, value))
+            /* Already done. */;
+        else if (!strcmp(attr->name, "segmentAlignment") && !strcmp(value, "true"))
+            /* Just check. */;
+        else if (!strcmp(attr->name, "startWithSAP") && !strcmp(value, "1"))
+            /* Just check. */;
+        else if (strcmp(attr->name, "id") &&
+                 strncmp(attr->name, "max", 3) &&
+                 strncmp(attr->name, "min", 3))
+            dash_log_unknown_attr(s, attr, value);
+    }
+
+    xml_for_each_child {
+        if (!strcmp(child->name, "SegmentTemplate"))
+            ret = dash_parse_segmenttemplate(s, period, &timeline, child);
+        else if (!strcmp(child->name, "SegmentList"))
+            ret = dash_parse_segmentlist(s, period, &timeline, child);
+        else if (!strcmp(child->name, "SegmentBase"))
+            ret = dash_parse_segmentbase(s, period, &timeline, child);
+        else if (!strcmp(child->name, "ContentProtection"))
+            ret = dash_parse_contentprotection(s, as, &cp, child);
+        else if (!strcmp(child->name, "BaseURL"))
+            ret = dash_parse_baseurl(s, &urls, child);
+        else if (!strcmp(child->name, "Role"))
+            ret = dash_parse_role(s, &par, child);
+        else if (!strcmp(child->name, "Viewpoint"))
+            ret = dash_parse_viewpoint(s, as, child);
+        else if (!strcmp(child->name, "SupplementalProperty") ||
+                 !strcmp(child->name, "EssentialProperty"))
+            ret = dash_parse_property(s, as, NULL, child);
+        else if (!strcmp(child->name, "Representation"))
+            ret = dash_parse_representation(s, period, as, urls, (timeline ? timeline : inherited_timeline), &par, child);
+        else if (!strcmp(child->name, "AudioChannelConfiguration"))
+            ret = dash_parse_audiochannelconfiguration(s, &par, child);
+        else if (!strcmp(child->name, "Label"))
+            ret = dash_parse_label(s, as, child);
+        else
+            dash_log_unknown_child(s, child);
 
-    ret = avio_read(pls->input, buf, buf_size);
-    if (ret > 0)
-        pls->cur_seg_offset += ret;
+        if (ret < 0)
+            goto out;
+    }
 
+out:
+    dash_unref_timeline(timeline);
+    dash_unref_urllist(urls);
     return ret;
 }
 
-static int open_input(DASHContext *c, struct representation *pls, struct fragment *seg)
+static av_cold int dash_parse_period(AVFormatContext *s,
+                                     DASHURLList *base_urls,
+                                     xmlNodePtr node)
 {
-    AVDictionary *opts = NULL;
-    char *url = NULL;
     int ret = 0;
+    DASHContext *c = s->priv_data;
+    DASHURLList *urls = dash_ref_urllist(base_urls);
+    DASHTimeline *timeline = NULL;
+    DASHPeriod *period;
+    int64_t duration = INT64_MAX;
+    DASHParameters par = DASH_PARAMETERS_INITIALIZER;
+
+    if ((ret = dash_push_id_node(s, &period, &c->periods, sizeof(DASHPeriod), node)) < 0)
+        goto out;
+
+    period->start_ts = 0;
+
+    xml_for_each_attr {
+        if (!strcmp(attr->name, "start"))
+            period->start_ts = dash_parse_duration(value, s);
+        else if (!strcmp(attr->name, "duration"))
+            duration = dash_parse_duration(value, s);
+        else if (!dash_parse_parameters(s, &par, attr, value))
+            /* Already done. */;
+        else if (strcmp(attr->name, "id"))
+            dash_log_unknown_attr(s, attr, value);
+    }
+
+    period->start_ts += c->availability_start_time;
+    period->end_ts = period->start_ts < INT64_MAX - duration
+        ? period->start_ts + duration
+        : INT64_MAX;
+    if (c->media_presentation_duration < 0)
+        s->duration = FFMAX(s->duration != AV_NOPTS_VALUE ? s->duration : 0, period->end_ts);
+    period->end_ts = FFMIN(period->end_ts, s->duration != AV_NOPTS_VALUE ? s->duration : 0);
+
+    /* INT64_MAX means infinity, ergo unknown duration. It has to be stored
+     * differently for format. */
+    if (INT64_MAX == s->duration)
+        s->duration = AV_NOPTS_VALUE;
+
+    /* Restrict duration of previous periods. */
+    for (unsigned i = 0; i < c->nb_periods; ++i) {
+        DASHPeriod *per = c->periods[i];
+        if (per->start_ts < period->start_ts)
+            per->end_ts = FFMIN(per->end_ts, period->start_ts);
+    }
+
+    if (period->end_ts <= period->start_ts) {
+        av_log(s, AV_LOG_DEBUG, "Ignoring empty Period %"PRId64" >= %"PRId64"\n",
+               period->start_ts, period->end_ts);
+        goto out;
+    }
+
+    xml_for_each_child {
+        if (!strcmp(child->name, "BaseURL"))
+            ret = dash_parse_baseurl(s, &urls, child);
+        else if (!strcmp(child->name, "SegmentTemplate"))
+            ret = dash_parse_segmenttemplate(s, period, &timeline, child);
+        else if (!strcmp(child->name, "SegmentList"))
+            ret = dash_parse_segmentlist(s, period, &timeline, child);
+        else if (!strcmp(child->name, "SegmentBase"))
+            ret = dash_parse_segmentbase(s, period, &timeline, child);
+        else if (!strcmp(child->name, "AdaptationSet"))
+            ret = dash_parse_adaptationset(s, period, urls, timeline, &par, child);
+        else if (!strcmp(child->name, "AssetIdentifier"))
+            ret = dash_parse_assetidentifier(s, period, child);
+        else
+            dash_log_unknown_child(s, child);
 
-    url = av_mallocz(c->max_url_size);
-    if (!url) {
-        ret = AVERROR(ENOMEM);
-        goto cleanup;
-    }
-
-    if (seg->size >= 0) {
-        /* try to restrict the HTTP request to the part we want
-         * (if this is in fact a HTTP request) */
-        av_dict_set_int(&opts, "offset", seg->url_offset, 0);
-        av_dict_set_int(&opts, "end_offset", seg->url_offset + seg->size, 0);
+        if (ret < 0)
+            goto out;
     }
 
-    ff_make_absolute_url(url, c->max_url_size, c->base_url, seg->url);
-    av_log(pls->parent, AV_LOG_VERBOSE, "DASH request for url '%s', offset %"PRId64"\n",
-           url, seg->url_offset);
-    ret = open_url(pls->parent, &pls->input, url, &c->avio_opts, opts, NULL);
-
-cleanup:
-    av_free(url);
-    av_dict_free(&opts);
-    pls->cur_seg_offset = 0;
-    pls->cur_seg_size = seg->size;
+out:
+    dash_unref_timeline(timeline);
+    dash_unref_urllist(urls);
     return ret;
 }
 
-static int update_init_section(struct representation *pls)
+static av_cold int dash_parse_programinformation(AVFormatContext *s, xmlNodePtr node)
 {
-    static const int max_init_section_size = 1024 * 1024;
-    DASHContext *c = pls->parent->priv_data;
-    int64_t sec_size;
-    int64_t urlsize;
-    int ret;
-
-    if (!pls->init_section || pls->init_sec_buf)
-        return 0;
+    xmlChar *lang = NULL;
 
-    ret = open_input(c, pls, pls->init_section);
-    if (ret < 0) {
-        av_log(pls->parent, AV_LOG_WARNING,
-               "Failed to open an initialization section\n");
-        return ret;
+    xml_for_each_attr {
+        if (!strcmp(attr->name, "lang")) {
+            lang = value;
+            value = NULL;
+        } else
+            dash_log_unknown_attr(s, attr, value);
     }
 
-    if (pls->init_section->size >= 0)
-        sec_size = pls->init_section->size;
-    else if ((urlsize = avio_size(pls->input)) >= 0)
-        sec_size = urlsize;
-    else
-        sec_size = max_init_section_size;
-
-    av_log(pls->parent, AV_LOG_DEBUG,
-           "Downloading an initialization section of size %"PRId64"\n",
-           sec_size);
+    xml_for_each_child {
+        const char *key = NULL;
+        xmlChar *value;
 
-    sec_size = FFMIN(sec_size, max_init_section_size);
-
-    av_fast_malloc(&pls->init_sec_buf, &pls->init_sec_buf_size, sec_size);
+        if (!(value = xmlNodeGetContent(child)))
+            continue;
 
-    ret = read_from_url(pls, pls->init_section, pls->init_sec_buf,
-                        pls->init_sec_buf_size);
-    ff_format_io_close(pls->parent, &pls->input);
+        if (!strcmp(child->name, "Title"))
+            key = "title";
+        else if (!strcmp(child->name, "Source"))
+            key = "source";
+        else if (!strcmp(child->name, "Copyright"))
+            key = "copyright";
+        else
+            dash_log_unknown_child(s, child);
 
-    if (ret < 0)
-        return ret;
+        if (key) {
+            char key_lang[100];
+            if (lang)
+                sprintf(key_lang, "%s-%s", key, lang);
+            av_dict_set(&s->metadata, lang ? key_lang : key, value, 0);
+        }
 
-    pls->init_sec_data_len = ret;
-    pls->init_sec_buf_read_offset = 0;
+        xmlFree(value);
+    }
 
+    xml_free(lang);
     return 0;
 }
 
-static int64_t seek_data(void *opaque, int64_t offset, int whence)
+static av_cold void dash_reset(AVFormatContext *s)
 {
-    struct representation *v = opaque;
-    if (v->n_fragments && !v->init_sec_data_len) {
-        return avio_seek(v->input, offset, whence);
-    }
+    DASHContext *c = s->priv_data;
+
+    /* Gets updated as we parse Periods. */
+    s->duration = AV_NOPTS_VALUE;
+    c->is_live = 0;
+    c->media_presentation_duration = INT64_MIN;
+
+    av_freep_arrayp(&c->reps, dash_free_representation);
+    av_freep_arrayp(&c->ass, dash_free_adaptationset);
+    av_freep_arrayp(&c->periods, dash_free_period);
+
+    av_freep(&c->location);
 
-    return AVERROR(ENOSYS);
+    xml_freep(&c->id);
+    xml_freep(&c->chain_next_location);
+    xml_freep(&c->fallback_location);
 }
 
-static int read_data(void *opaque, uint8_t *buf, int buf_size)
+static av_cold int dash_parse_mpd(AVFormatContext *s,
+                                  DASHURLList *base_urls,
+                                  xmlNodePtr node)
 {
     int ret = 0;
-    struct representation *v = opaque;
-    DASHContext *c = v->parent->priv_data;
-
-restart:
-    if (!v->input) {
-        free_fragment(&v->cur_seg);
-        v->cur_seg = get_current_fragment(v);
-        if (!v->cur_seg) {
-            ret = AVERROR_EOF;
-            goto end;
-        }
-
-        /* load/update Media Initialization Section, if any */
-        ret = update_init_section(v);
-        if (ret)
-            goto end;
+    DASHContext *c = s->priv_data;
+    DASHURLList *urls = dash_ref_urllist(base_urls);
 
-        ret = open_input(c, v, v->cur_seg);
-        if (ret < 0) {
-            if (ff_check_interrupt(c->interrupt_callback)) {
-                ret = AVERROR_EXIT;
-                goto end;
-            }
-            av_log(v->parent, AV_LOG_WARNING, "Failed to open fragment of playlist\n");
-            v->cur_seq_no++;
-            goto restart;
-        }
+    /* Nullify periods.
+     * TODO: Maybe they sould be cleaned up after parsing. */
+    for (unsigned i = 0; i < c->nb_periods; ++i) {
+        DASHPeriod *period = c->periods[i];
+        period->start_ts = period->end_ts = 0;
     }
 
-    if (v->init_sec_buf_read_offset < v->init_sec_data_len) {
-        /* Push init section out first before first actual fragment */
-        int copy_size = FFMIN(v->init_sec_data_len - v->init_sec_buf_read_offset, buf_size);
-        memcpy(buf, v->init_sec_buf, copy_size);
-        v->init_sec_buf_read_offset += copy_size;
-        ret = copy_size;
-        goto end;
+    {
+        xmlChar *id = xmlGetNoNsProp(node, "id");
+        if (!c->id || !id || strcmp(c->id, id)) {
+            dash_reset(s);
+            c->id = id;
+        } else {
+            xmlFree(id);
+        }
     }
 
-    /* check the v->cur_seg, if it is null, get current and double check if the new v->cur_seg*/
-    if (!v->cur_seg) {
-        v->cur_seg = get_current_fragment(v);
-    }
-    if (!v->cur_seg) {
-        ret = AVERROR_EOF;
-        goto end;
-    }
-    ret = read_from_url(v, v->cur_seg, buf, buf_size);
-    if (ret > 0)
-        goto end;
+    xml_for_each_attr {
+        if (!strcmp(attr->name, "type")) {
+            /* https://livesim.dashif.org/livesim/scte35_2/testpic_2s/Manifest.mpd */
+            if (!strcmp(value, "dynamic"))
+                c->is_live = 1;
+            else if (!strcmp(value, "static"))
+                c->is_live = 0;
+            else
+                dash_log_invalid_attr_value(s, attr, value);
+        } else if (!strcmp(attr->name, "availabilityStartTime"))
+            c->availability_start_time = dash_parse_date(value, s);
+        else if (!strcmp(attr->name, "availabilityEndTime"))
+            c->availability_end_time  = dash_parse_date(value, s);
+        else if (!strcmp(attr->name, "publishTime")) {
+            c->publish_time = dash_parse_date(value, s);
+            /* Take the easy way. */
+            av_dict_set(&s->metadata, "creation_time", value, 0);
+        } else if (!strcmp(attr->name, "minimumUpdatePeriod"))
+            c->min_update_period = dash_parse_duration(value, s);
+        else if (!strcmp(attr->name, "maxSegmentDuration"))
+            c->max_segment_duration = dash_parse_duration(value, s);
+        else if (!strcmp(attr->name, "minBufferTime"))
+            c->min_buffer_time = dash_parse_duration(value, s);
+        else if (!strcmp(attr->name, "timeShiftBufferDepth"))
+            c->time_shift_buffer_depth = dash_parse_duration(value, s);
+        else if (!strcmp(attr->name, "mediaPresentationDuration"))
+            s->duration = c->media_presentation_duration = dash_parse_duration(value, s);
+        else if (strcmp(attr->name, "id") &&
+                 strcmp(attr->name, "profiles") &&
+                 strcmp(attr->name, "schemaLocation"))
+            dash_log_unknown_attr(s, attr, value);
+    }
+
+    xml_for_each_child {
+        if (!strcmp(child->name, "ProgramInformation"))
+            ret = dash_parse_programinformation(s, child);
+        else if (!strcmp(child->name, "Location"))
+            ret = dash_parse_location(s, child);
+        else if (!strcmp(child->name, "BaseURL"))
+            ret = dash_parse_baseurl(s, &urls, child);
+        else if (!strcmp(child->name, "Period"))
+            ret = dash_parse_period(s, urls, child);
+        else if (!strcmp(child->name, "UTCTiming"))
+            ret = dash_parse_utctiming(s, child);
+        else if (!strcmp(child->name, "SupplementalProperty") ||
+                 !strcmp(child->name, "EssentialProperty"))
+            ret = dash_parse_property(s, NULL, NULL, child);
+        else
+            dash_log_unknown_child(s, child);
 
-    if (c->is_live || v->cur_seq_no < v->last_seq_no) {
-        if (!v->is_restart_needed)
-            v->cur_seq_no++;
-        v->is_restart_needed = 1;
+        if (ret < 0)
+            goto out;
     }
 
-end:
+out:
+    dash_unref_urllist(urls);
     return ret;
 }
 
-static int save_avio_options(AVFormatContext *s)
+/**
+ * Remove filename component from an URL.
+ */
+static int ff_make_absolute_head_urla(char **out_url, const char *url)
 {
-    DASHContext *c = s->priv_data;
-    const char *opts[] = {
-        "headers", "user_agent", "cookies", "http_proxy", "referer", "rw_timeout", "icy", NULL };
-    const char **opt = opts;
-    uint8_t *buf = NULL;
-    int ret = 0;
+    int ret;
 
-    while (*opt) {
-        if (av_opt_get(s->pb, *opt, AV_OPT_SEARCH_CHILDREN, &buf) >= 0) {
-            if (buf[0] != '\0') {
-                ret = av_dict_set(&c->avio_opts, *opt, buf, AV_DICT_DONT_STRDUP_VAL);
-                if (ret < 0)
-                    return ret;
-            } else {
-                av_freep(&buf);
-            }
-        }
-        opt++;
+    if (0 <= (ret = ff_make_absolute_urla(out_url, url, "./"))) {
+        char *p = *out_url;
+        size_t len = strlen(p);
+
+        if (3 <= len && !memcmp(p + len - 3, "/./", 4))
+            p[len - 2] = '\0';
     }
 
     return ret;
 }
 
-static int nested_io_open(AVFormatContext *s, AVIOContext **pb, const char *url,
-                          int flags, AVDictionary **opts)
-{
-    av_log(s, AV_LOG_ERROR,
-           "A DASH playlist item '%s' referred to an external file '%s'. "
-           "Opening this file was forbidden for security reasons\n",
-           s->url, url);
-    return AVERROR(EPERM);
-}
-
-static void close_demux_for_component(struct representation *pls)
-{
-    /* note: the internal buffer could have changed */
-    av_freep(&pls->pb.buffer);
-    memset(&pls->pb, 0x00, sizeof(AVIOContext));
-    pls->ctx->pb = NULL;
-    avformat_close_input(&pls->ctx);
-}
-
-static int reopen_demux_for_component(AVFormatContext *s, struct representation *pls)
+static av_cold int dash_parse_root(AVFormatContext *s, xmlNodePtr node)
 {
+    int ret = 0;
+    DASHURLList *urls = NULL;
     DASHContext *c = s->priv_data;
-    ff_const59 AVInputFormat *in_fmt = NULL;
-    AVDictionary  *in_fmt_opts = NULL;
-    uint8_t *avio_ctx_buffer  = NULL;
-    int ret = 0, i;
-
-    if (pls->ctx) {
-        close_demux_for_component(pls);
-    }
 
-    if (ff_check_interrupt(&s->interrupt_callback)) {
-        ret = AVERROR_EXIT;
-        goto fail;
+    if (!node ||
+        strcmp(node->name, "MPD") ||
+        !node->ns ||
+        strcmp(node->ns->href, "urn:mpeg:dash:schema:mpd:2011"))
+    {
+        av_log(s, AV_LOG_ERROR, "Not an MPD\n");
+        return AVERROR_INVALIDDATA;
     }
 
-    if (!(pls->ctx = avformat_alloc_context())) {
+    if (!(urls = dash_new_urllist(1))) {
         ret = AVERROR(ENOMEM);
-        goto fail;
+        goto out;
     }
 
-    avio_ctx_buffer  = av_malloc(INITIAL_BUFFER_SIZE);
-    if (!avio_ctx_buffer ) {
-        ret = AVERROR(ENOMEM);
-        avformat_free_context(pls->ctx);
-        pls->ctx = NULL;
-        goto fail;
-    }
-    ffio_init_context(&pls->pb, avio_ctx_buffer, INITIAL_BUFFER_SIZE, 0,
-                      pls, read_data, NULL, c->is_live ? NULL : seek_data);
-    pls->pb.seekable = 0;
-
-    if ((ret = ff_copy_whiteblacklists(pls->ctx, s)) < 0)
-        goto fail;
-
-    pls->ctx->flags = AVFMT_FLAG_CUSTOM_IO;
-    pls->ctx->probesize = s->probesize > 0 ? s->probesize : 1024 * 4;
-    pls->ctx->max_analyze_duration = s->max_analyze_duration > 0 ? s->max_analyze_duration : 4 * AV_TIME_BASE;
-    pls->ctx->interrupt_callback = s->interrupt_callback;
-    ret = av_probe_input_buffer(&pls->pb, &in_fmt, "", NULL, 0, 0);
-    if (ret < 0) {
-        av_log(s, AV_LOG_ERROR, "Error when loading first fragment of playlist\n");
-        avformat_free_context(pls->ctx);
-        pls->ctx = NULL;
-        goto fail;
-    }
-
-    pls->ctx->pb = &pls->pb;
-    pls->ctx->io_open  = nested_io_open;
-
-    // provide additional information from mpd if available
-    ret = avformat_open_input(&pls->ctx, "", in_fmt, &in_fmt_opts); //pls->init_section->url
-    av_dict_free(&in_fmt_opts);
-    if (ret < 0)
-        goto fail;
-    if (pls->n_fragments) {
-#if FF_API_R_FRAME_RATE
-        if (pls->framerate.den) {
-            for (i = 0; i < pls->ctx->nb_streams; i++)
-                pls->ctx->streams[i]->r_frame_rate = pls->framerate;
-        }
-#endif
-        ret = avformat_find_stream_info(pls->ctx, NULL);
-        if (ret < 0)
-            goto fail;
-    }
+    if ((ret = ff_make_absolute_head_urla(&urls->elems[0], c->location)) < 0)
+        goto out;
 
-fail:
+    if ((ret = dash_parse_mpd(s, urls, node)) < 0)
+        goto out;
+
+out:
+    dash_unref_urllist(urls);
     return ret;
 }
 
-static int open_demux_for_component(AVFormatContext *s, struct representation *pls)
+static av_cold void dash_libxml_error_handler(void *opaque, const char *fmt, ...)
+{
+    AVFormatContext *s = opaque;
+    va_list ap;
+
+    va_start(ap, fmt);
+    av_vlog(s, AV_LOG_ERROR, fmt, ap);
+    va_end(ap);
+}
+
+static av_cold int dash_open_manifest(AVFormatContext *s)
 {
     int ret = 0;
-    int i;
+    DASHContext *c = s->priv_data;
+    xmlParserCtxtPtr xml;
+    AVIOContext *pb;
+    AVDictionary *opts = NULL;
+    uint8_t *location;
 
-    pls->parent = s;
-    pls->cur_seq_no  = calc_cur_seg_no(s, pls);
+    av_dict_set(&opts, "icy", "0", 0);
+    ret = s->io_open(s, &pb, c->location, AVIO_FLAG_READ, &opts);
+    av_dict_free(&opts);
+    if (ret < 0)
+        return ret;
 
-    if (!pls->last_seq_no) {
-        pls->last_seq_no = calc_max_seg_no(pls, s->priv_data);
-    }
+    xmlSetGenericErrorFunc(s, dash_libxml_error_handler);
 
-    ret = reopen_demux_for_component(s, pls);
-    if (ret < 0) {
-        goto fail;
-    }
-    for (i = 0; i < pls->ctx->nb_streams; i++) {
-        AVStream *st = avformat_new_stream(s, NULL);
-        AVStream *ist = pls->ctx->streams[i];
-        if (!st) {
-            ret = AVERROR(ENOMEM);
-            goto fail;
-        }
-        st->id = i;
-        avcodec_parameters_copy(st->codecpar, ist->codecpar);
-        avpriv_set_pts_info(st, ist->pts_wrap_bits, ist->time_base.num, ist->time_base.den);
+    /* Why not SAX? DASH-IF may standardize patching that obviously requires us
+     * to maintain DOM. */
+    for (xml = NULL;;) {
+        char buf[1 << 14];
 
-        // copy disposition
-        st->disposition = ist->disposition;
+        /* libXML2 needs at least 4 bytes at the beginnig to being able to
+         * initialize its parsing context. */
+        if (0 < (ret = (xml ? avio_read_partial : avio_read)(pb, buf, (xml ? sizeof(buf) : sizeof("BOM"))))) {
+            /* Context is initialized by the first read call. */
+            if (!xml) {
+                if ((xml = xmlCreatePushParserCtxt(NULL, NULL, buf, ret, NULL)))
+                    continue;
+            } else {
+                if (!xmlParseChunk(xml, buf, ret, 0 /* Terminate? */))
+                    continue;
 
-        // copy side data
-        for (int i = 0; i < ist->nb_side_data; i++) {
-            const AVPacketSideData *sd_src = &ist->side_data[i];
-            uint8_t *dst_data;
+            parse_error:
+                av_log(s, AV_LOG_ERROR, "Failed to parse manifest file\n");
+                ret = AVERROR_INVALIDDATA;
+                goto out;
+            }
+        } else if (ret == AVERROR_EOF) {
+            if (!xmlParseChunk(xml, NULL, 0, 1 /* Terminate? */))
+                break;
 
-            dst_data = av_stream_new_side_data(st, sd_src->type, sd_src->size);
-            if (!dst_data)
-                return AVERROR(ENOMEM);
-            memcpy(dst_data, sd_src->data, sd_src->size);
+            goto parse_error;
         }
-    }
-
-    return 0;
-fail:
-    return ret;
-}
 
-static int is_common_init_section_exist(struct representation **pls, int n_pls)
-{
-    struct fragment *first_init_section = pls[0]->init_section;
-    char *url =NULL;
-    int64_t url_offset = -1;
-    int64_t size = -1;
-    int i = 0;
+        av_log(s, AV_LOG_ERROR, "Failed to read manifest file\n");
+        goto out;
+    }
 
-    if (first_init_section == NULL || n_pls == 0)
-        return 0;
+    /* For HTTP 3XX redirects standard states that the redirected location
+     * should be used for updates. We are lazy and just check for "location". */
+    if (0 <= av_opt_get(pb, "location", AV_OPT_SEARCH_CHILDREN, &location)) {
+        (void)dash_set_location(s, location);
+        av_free(location);
+    }
 
-    url = first_init_section->url;
-    url_offset = first_init_section->url_offset;
-    size = pls[0]->init_section->size;
-    for (i=0;i<n_pls;i++) {
-        if (!pls[i]->init_section)
-            continue;
+    ret = dash_parse_root(s, xmlDocGetRootElement(xml->myDoc));
 
-        if (av_strcasecmp(pls[i]->init_section->url, url) ||
-            pls[i]->init_section->url_offset != url_offset ||
-            pls[i]->init_section->size != size) {
-            return 0;
-        }
+    if (c->is_live) {
+        int64_t accuracy = c->min_update_period / 20; /* 5% */
+        c->next_update = av_gettime() +
+                         (av_lfg_get(&c->rnd) % accuracy + 1) +
+                         (c->min_update_period - accuracy);
+    } else {
+        c->next_update = 0;
     }
-    return 1;
-}
 
-static int copy_init_section(struct representation *rep_dest, struct representation *rep_src)
-{
-    rep_dest->init_sec_buf = av_mallocz(rep_src->init_sec_buf_size);
-    if (!rep_dest->init_sec_buf) {
-        av_log(rep_dest->ctx, AV_LOG_WARNING, "Cannot alloc memory for init_sec_buf\n");
-        return AVERROR(ENOMEM);
+out:
+    if (xml) {
+        if (xml->myDoc)
+            xmlFreeDoc(xml->myDoc);
+        xmlFreeParserCtxt(xml);
     }
-    memcpy(rep_dest->init_sec_buf, rep_src->init_sec_buf, rep_src->init_sec_data_len);
-    rep_dest->init_sec_buf_size = rep_src->init_sec_buf_size;
-    rep_dest->init_sec_data_len = rep_src->init_sec_data_len;
-    rep_dest->cur_timestamp = rep_src->cur_timestamp;
-
-    return 0;
-}
 
-static int dash_close(AVFormatContext *s);
+    /* Reset handlers so passed references to AVFormatContext will not survive. */
+    xmlSetGenericErrorFunc(NULL, NULL);
 
-static void move_metadata(AVStream *st, const char *key, char **value)
-{
-    if (*value) {
-        av_dict_set(&st->metadata, key, *value, AV_DICT_DONT_STRDUP_VAL);
-        *value = NULL;
-    }
+    ff_format_io_close(s, &pb);
+    return ret;
 }
 
-static int dash_read_header(AVFormatContext *s)
+static av_cold int dash_close(AVFormatContext *s)
 {
     DASHContext *c = s->priv_data;
-    struct representation *rep;
-    AVProgram *program;
-    int ret = 0;
-    int stream_index = 0;
-    int i;
 
-    c->interrupt_callback = &s->interrupt_callback;
+    dash_reset(s);
 
-    if ((ret = save_avio_options(s)) < 0)
-        goto fail;
+    av_dict_free(&c->protocol_opts);
 
-    if ((ret = parse_manifest(s, s->url, s->pb)) < 0)
-        goto fail;
+    return 0;
+}
 
-    /* If this isn't a live stream, fill the total duration of the
-     * stream. */
-    if (!c->is_live) {
-        s->duration = (int64_t) c->media_presentation_duration * AV_TIME_BASE;
-    } else {
-        av_dict_set(&c->avio_opts, "seekable", "0", 0);
-    }
+static av_cold int dash_save_protocol_options(AVFormatContext *s)
+{
+    static const char OPTIONS[] =
+        "headers\0" "http_proxy\0" "user_agent\0" "cookies\0" "referer\0"
+        "rw_timeout\0" "icy\0";
+
+    DASHContext *c = s->priv_data;
 
-    if(c->n_videos)
-        c->is_init_section_common_video = is_common_init_section_exist(c->videos, c->n_videos);
+    for (const char *opt = OPTIONS; *opt; opt += strlen(opt) + 1 /* NUL */) {
+        uint8_t *buf;
 
-    /* Open the demuxer for video and audio components if available */
-    for (i = 0; i < c->n_videos; i++) {
-        rep = c->videos[i];
-        if (i > 0 && c->is_init_section_common_video) {
-            ret = copy_init_section(rep, c->videos[0]);
+        if (0 <= av_opt_get(s->pb, opt, AV_OPT_SEARCH_CHILDREN | AV_OPT_ALLOW_NULL, &buf) && buf) {
+            int ret = av_dict_set(&c->protocol_opts, opt, buf,
+                                  AV_DICT_DONT_OVERWRITE | AV_DICT_DONT_STRDUP_VAL);
             if (ret < 0)
-                goto fail;
+                return ret;
         }
-        ret = open_demux_for_component(s, rep);
-
-        if (ret)
-            goto fail;
-        rep->stream_index = stream_index;
-        ++stream_index;
     }
 
-    if(c->n_audios)
-        c->is_init_section_common_audio = is_common_init_section_exist(c->audios, c->n_audios);
-
-    for (i = 0; i < c->n_audios; i++) {
-        rep = c->audios[i];
-        if (i > 0 && c->is_init_section_common_audio) {
-            ret = copy_init_section(rep, c->audios[0]);
-            if (ret < 0)
-                goto fail;
-        }
-        ret = open_demux_for_component(s, rep);
+    return 0;
+}
 
-        if (ret)
-            goto fail;
-        rep->stream_index = stream_index;
-        ++stream_index;
-    }
+static av_cold int dash_read_header(AVFormatContext *s)
+{
+    int ret = 0;
+    DASHContext *c = s->priv_data;
 
-    if (c->n_subtitles)
-        c->is_init_section_common_subtitle = is_common_init_section_exist(c->subtitles, c->n_subtitles);
+    if ((ret = dash_set_location(s, s->url)) < 0)
+        goto out;
 
-    for (i = 0; i < c->n_subtitles; i++) {
-        rep = c->subtitles[i];
-        if (i > 0 && c->is_init_section_common_subtitle) {
-            ret = copy_init_section(rep, c->subtitles[0]);
-            if (ret < 0)
-                goto fail;
-        }
-        ret = open_demux_for_component(s, rep);
+    /* Signal that we may create additional streams as time pasts. */
+    s->ctx_flags |= AVFMTCTX_NOHEADER;
 
-        if (ret)
-            goto fail;
-        rep->stream_index = stream_index;
-        ++stream_index;
-    }
+    if ((ret = dash_save_protocol_options(s)) < 0)
+        goto out;
 
-    if (!stream_index) {
-        ret = AVERROR_INVALIDDATA;
-        goto fail;
-    }
+    av_lfg_init(&c->rnd, av_get_random_seed());
 
-    /* Create a program */
-    program = av_new_program(s, 0);
-    if (!program) {
-        ret = AVERROR(ENOMEM);
-        goto fail;
-    }
-
-    for (i = 0; i < c->n_videos; i++) {
-        rep = c->videos[i];
-        av_program_add_stream_index(s, 0, rep->stream_index);
-        rep->assoc_stream = s->streams[rep->stream_index];
-        if (rep->bandwidth > 0)
-            av_dict_set_int(&rep->assoc_stream->metadata, "variant_bitrate", rep->bandwidth, 0);
-        move_metadata(rep->assoc_stream, "id", &rep->id);
-    }
-    for (i = 0; i < c->n_audios; i++) {
-        rep = c->audios[i];
-        av_program_add_stream_index(s, 0, rep->stream_index);
-        rep->assoc_stream = s->streams[rep->stream_index];
-        if (rep->bandwidth > 0)
-            av_dict_set_int(&rep->assoc_stream->metadata, "variant_bitrate", rep->bandwidth, 0);
-        move_metadata(rep->assoc_stream, "id", &rep->id);
-        move_metadata(rep->assoc_stream, "language", &rep->lang);
-    }
-    for (i = 0; i < c->n_subtitles; i++) {
-        rep = c->subtitles[i];
-        av_program_add_stream_index(s, 0, rep->stream_index);
-        rep->assoc_stream = s->streams[rep->stream_index];
-        move_metadata(rep->assoc_stream, "id", &rep->id);
-        move_metadata(rep->assoc_stream, "language", &rep->lang);
-    }
+    if ((ret = dash_open_manifest(s)) < 0)
+        goto out;
 
-    return 0;
-fail:
-    dash_close(s);
+out:
+    if (ret < 0)
+        dash_close(s);
     return ret;
 }
 
-static void recheck_discard_flags(AVFormatContext *s, struct representation **p, int n)
+static DASHRepresentation *dash_get_read_next_representation(AVFormatContext *s)
 {
-    int i, j;
+    DASHContext *c = s->priv_data;
+    DASHRepresentation *best_rep = NULL;
 
-    for (i = 0; i < n; i++) {
-        struct representation *pls = p[i];
-        int needed = !pls->assoc_stream || pls->assoc_stream->discard < AVDISCARD_ALL;
+    for (unsigned i = 0; i < c->nb_reps; ++i) {
+        DASHRepresentation *rep = c->reps[i];
+        int needed = 0;
 
-        if (needed && !pls->ctx) {
-            pls->cur_seg_offset = 0;
-            pls->init_sec_buf_read_offset = 0;
-            /* Catch up */
-            for (j = 0; j < n; j++) {
-                pls->cur_seq_no = FFMAX(pls->cur_seq_no, p[j]->cur_seq_no);
-            }
-            reopen_demux_for_component(s, pls);
-            av_log(s, AV_LOG_INFO, "Now receiving stream_index %d\n", pls->stream_index);
-        } else if (!needed && pls->ctx) {
-            close_demux_for_component(pls);
-            ff_format_io_close(pls->parent, &pls->input);
-            av_log(s, AV_LOG_INFO, "No longer receiving stream_index %d\n", pls->stream_index);
+        /* Subdemuxer not opened for this representation, so we are not
+         * interested in receiving segments for this. */
+        if (!rep->ic)
+            continue;
+
+        /* Check if any of the streams is needed. */
+        for (unsigned k = 0; k < rep->nb_streams; ++k) {
+            AVStream *ost = rep->ostreams[k];
+            if ((needed = ost->discard < AVDISCARD_ALL))
+                break;
         }
+
+        if (!needed)
+            continue;
+
+        /* A toy scheduler. */
+        if (!best_rep || rep->last_pts < best_rep->last_pts)
+            best_rep = rep;
     }
+
+    return best_rep;
 }
 
 static int dash_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
+    int ret;
+    DASHRepresentation *rep;
+    AVStream *ist, /* --packet--> */ *ost;
     DASHContext *c = s->priv_data;
-    int ret = 0, i;
-    int64_t mints = 0;
-    struct representation *cur = NULL;
-    struct representation *rep = NULL;
-
-    recheck_discard_flags(s, c->videos, c->n_videos);
-    recheck_discard_flags(s, c->audios, c->n_audios);
-    recheck_discard_flags(s, c->subtitles, c->n_subtitles);
-
-    for (i = 0; i < c->n_videos; i++) {
-        rep = c->videos[i];
-        if (!rep->ctx)
-            continue;
-        if (!cur || rep->cur_timestamp < mints) {
-            cur = rep;
-            mints = rep->cur_timestamp;
+
+    if (c->next_update && c->next_update <= av_gettime())
+        if ((ret = dash_open_manifest(s)) < 0) {
+            c->next_update = av_gettime() * (60 * MICROSEC_PER_SEC) /* 1 min */;
+            av_log(s, AV_LOG_ERROR, "Failed to update manifest\n");
         }
-    }
-    for (i = 0; i < c->n_audios; i++) {
-        rep = c->audios[i];
-        if (!rep->ctx)
-            continue;
-        if (!cur || rep->cur_timestamp < mints) {
-            cur = rep;
-            mints = rep->cur_timestamp;
+
+    /* Find a representation where we can read from. */
+    for (;;) {
+        if (!(rep = dash_get_read_next_representation(s))) {
+            /* Load next manifest, if any. */
+            if (c->chain_next_location) {
+                if ((ret = dash_set_location(s, c->chain_next_location)) < 0)
+                    return ret;
+                xml_freep(&c->chain_next_location);
+
+                if ((ret = dash_open_manifest(s)) < 0)
+                    return ret;
+
+                continue;
+            }
+
+            return AVERROR_EOF;
         }
-    }
 
-    for (i = 0; i < c->n_subtitles; i++) {
-        rep = c->subtitles[i];
-        if (!rep->ctx)
+        if ((!rep->ic->iformat &&
+             (ret = dash_subdemuxer_open(rep)) < 0) ||
+            (ret = av_read_frame(rep->ic, pkt)) < 0)
+        {
+            av_log(s, AVERROR_EOF != ret ? AV_LOG_ERROR : AV_LOG_DEBUG,
+                   "Failed to read representation '%s': %s\n",
+                   rep->id, av_err2str(ret));
+            dash_subdemuxer_close(rep);
             continue;
-        if (!cur || rep->cur_timestamp < mints) {
-            cur = rep;
-            mints = rep->cur_timestamp;
         }
-    }
 
-    if (!cur) {
-        return AVERROR_INVALIDDATA;
-    }
-    while (!ff_check_interrupt(c->interrupt_callback) && !ret) {
-        ret = av_read_frame(cur->ctx, pkt);
-        if (ret >= 0) {
-            /* If we got a packet, return it */
-            cur->cur_timestamp = av_rescale(pkt->pts, (int64_t)cur->ctx->streams[0]->time_base.num * 90000, cur->ctx->streams[0]->time_base.den);
-            pkt->stream_index = cur->stream_index;
-            return 0;
-        }
-        if (cur->is_restart_needed) {
-            cur->cur_seg_offset = 0;
-            cur->init_sec_buf_read_offset = 0;
-            ff_format_io_close(cur->parent, &cur->input);
-            ret = reopen_demux_for_component(s, cur);
-            cur->is_restart_needed = 0;
-        }
+        break;
     }
-    return AVERROR_EOF;
-}
 
-static int dash_close(AVFormatContext *s)
-{
-    DASHContext *c = s->priv_data;
-    free_audio_list(c);
-    free_video_list(c);
-    free_subtitle_list(c);
-    av_dict_free(&c->avio_opts);
-    av_freep(&c->base_url);
-    return 0;
-}
+    ist = rep->ic->streams[pkt->stream_index];
 
-static int dash_seek(AVFormatContext *s, struct representation *pls, int64_t seek_pos_msec, int flags, int dry_run)
-{
-    int ret = 0;
-    int i = 0;
-    int j = 0;
-    int64_t duration = 0;
+    if (/* New stream had been created by the underlying subdemuxer. */
+        rep->nb_streams <= pkt->stream_index ||
+        /* Something changed. */
+        (ist->event_flags & AVSTREAM_EVENT_FLAG_METADATA_UPDATED))
+        if ((ret = dash_subdemuxer_update(rep)) < 0)
+            return ret;
 
-    av_log(pls->parent, AV_LOG_VERBOSE, "DASH seek pos[%"PRId64"ms] %s\n",
-           seek_pos_msec, dry_run ? " (dry)" : "");
-
-    // single fragment mode
-    if (pls->n_fragments == 1) {
-        pls->cur_timestamp = 0;
-        pls->cur_seg_offset = 0;
-        if (dry_run)
-            return 0;
-        ff_read_frame_flush(pls->ctx);
-        return av_seek_frame(pls->ctx, -1, seek_pos_msec * 1000, flags);
-    }
-
-    ff_format_io_close(pls->parent, &pls->input);
-
-    // find the nearest fragment
-    if (pls->n_timelines > 0 && pls->fragment_timescale > 0) {
-        int64_t num = pls->first_seq_no;
-        av_log(pls->parent, AV_LOG_VERBOSE, "dash_seek with SegmentTimeline start n_timelines[%d] "
-               "last_seq_no[%"PRId64"].\n",
-               (int)pls->n_timelines, (int64_t)pls->last_seq_no);
-        for (i = 0; i < pls->n_timelines; i++) {
-            if (pls->timelines[i]->starttime > 0) {
-                duration = pls->timelines[i]->starttime;
-            }
-            duration += pls->timelines[i]->duration;
-            if (seek_pos_msec < ((duration * 1000) /  pls->fragment_timescale)) {
-                goto set_seq_num;
-            }
-            for (j = 0; j < pls->timelines[i]->repeat; j++) {
-                duration += pls->timelines[i]->duration;
-                num++;
-                if (seek_pos_msec < ((duration * 1000) /  pls->fragment_timescale)) {
-                    goto set_seq_num;
-                }
-            }
-            num++;
-        }
+    /* Make packet timestamps comparable to each other. */
+    rep->last_pts = av_rescale_q(pkt->pts + pkt->duration, ist->time_base, AV_TIME_BASE_Q);
 
-set_seq_num:
-        pls->cur_seq_no = num > pls->last_seq_no ? pls->last_seq_no : num;
-        av_log(pls->parent, AV_LOG_VERBOSE, "dash_seek with SegmentTimeline end cur_seq_no[%"PRId64"].\n",
-               (int64_t)pls->cur_seq_no);
-    } else if (pls->fragment_duration > 0) {
-        pls->cur_seq_no = pls->first_seq_no + ((seek_pos_msec * pls->fragment_timescale) / pls->fragment_duration) / 1000;
-    } else {
-        av_log(pls->parent, AV_LOG_ERROR, "dash_seek missing timeline or fragment_duration\n");
-        pls->cur_seq_no = pls->first_seq_no;
-    }
-    pls->cur_timestamp = 0;
-    pls->cur_seg_offset = 0;
-    pls->init_sec_buf_read_offset = 0;
-    ret = dry_run ? 0 : reopen_demux_for_component(s, pls);
+    ost = rep->ostreams[pkt->stream_index];
+    if (ost->codecpar->codec_type != ist->codecpar->codec_type ||
+        ost->codecpar->codec_id   != ist->codecpar->codec_id   ||
+        ost->codecpar->codec_tag  != ist->codecpar->codec_tag)
+        if ((ret = dash_subdemuxer_update(rep)) < 0)
+            return ret;
 
-    return ret;
+    /* Translate stream_index from inner to outer context. */
+    pkt->stream_index = ost->index;
+
+    return 0;
 }
 
 static int dash_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
 {
-    int ret = 0, i;
+    int ret = 0;
     DASHContext *c = s->priv_data;
-    int64_t seek_pos_msec = av_rescale_rnd(timestamp, 1000,
-                                           s->streams[stream_index]->time_base.den,
-                                           flags & AVSEEK_FLAG_BACKWARD ?
-                                           AV_ROUND_DOWN : AV_ROUND_UP);
-    if ((flags & AVSEEK_FLAG_BYTE) || c->is_live)
+    AVStream *st;
+    int64_t now_ts;
+
+    if (flags & AVSEEK_FLAG_BYTE)
         return AVERROR(ENOSYS);
 
-    /* Seek in discarded streams with dry_run=1 to avoid reopening them */
-    for (i = 0; i < c->n_videos; i++) {
-        if (!ret)
-            ret = dash_seek(s, c->videos[i], seek_pos_msec, flags, !c->videos[i]->ctx);
-    }
-    for (i = 0; i < c->n_audios; i++) {
-        if (!ret)
-            ret = dash_seek(s, c->audios[i], seek_pos_msec, flags, !c->audios[i]->ctx);
-    }
-    for (i = 0; i < c->n_subtitles; i++) {
-        if (!ret)
-            ret = dash_seek(s, c->subtitles[i], seek_pos_msec, flags, !c->subtitles[i]->ctx);
+    st = s->streams[stream_index];
+    now_ts = av_rescale_q_rnd(timestamp, st->time_base, AV_TIME_BASE_Q,
+                              (flags & AVSEEK_FLAG_BACKWARD)
+                                  ? AV_ROUND_DOWN : AV_ROUND_UP);
+
+    for (unsigned i = 0; i < c->nb_reps; ++i) {
+        DASHRepresentation *rep = c->reps[i];
+
+        if (!rep->ic)
+            continue;
+
+        rep->last_pts = AV_NOPTS_VALUE;
+
+        rep->read_ts = c->start_ts + now_ts;
+
+        if ((ret = av_seek_frame(rep->ic, -1, now_ts, flags)) < 0) {
+            av_log(s, AV_LOG_ERROR, "Failed to seek subdemuxer\n");
+            /* abort(); */
+        }
+
+        dash_subdemuxer_flush(rep);
     }
 
     return ret;
 }
 
-static int dash_probe(const AVProbeData *p)
+static av_cold int dash_probe(const AVProbeData *p)
 {
-    if (!av_stristr(p->buf, "<MPD"))
-        return 0;
-
-    if (av_stristr(p->buf, "dash:profile:isoff-on-demand:2011") ||
-        av_stristr(p->buf, "dash:profile:isoff-live:2011") ||
-        av_stristr(p->buf, "dash:profile:isoff-live:2012") ||
-        av_stristr(p->buf, "dash:profile:isoff-main:2011") ||
-        av_stristr(p->buf, "3GPP:PSS:profile:DASH1")) {
+    if (strstr(p->buf, "<?xml") &&
+        strstr(p->buf, "<MPD"))
         return AVPROBE_SCORE_MAX;
-    }
-    if (av_stristr(p->buf, "dash:profile")) {
+
+    if (p->mime_type && !strncmp(p->mime_type, "application/dash+xml", 20))
         return AVPROBE_SCORE_MAX;
-    }
 
     return 0;
 }
 
 #define OFFSET(x) offsetof(DASHContext, x)
-#define FLAGS AV_OPT_FLAG_DECODING_PARAM
 static const AVOption dash_options[] = {
-    {"allowed_extensions", "List of file extensions that dash is allowed to access",
-        OFFSET(allowed_extensions), AV_OPT_TYPE_STRING,
-        {.str = "aac,m4a,m4s,m4v,mov,mp4,webm,ts"},
-        INT_MIN, INT_MAX, FLAGS},
-    {NULL}
+    { "connections", "Number of segment requests on the fly (per representation)",
+        OFFSET(nb_connections), AV_OPT_TYPE_INT,
+        { .i64 = 1 }, .min = 1, .max = UINT_MAX, .flags = AV_OPT_FLAG_DECODING_PARAM },
+    { "protocol_opts", "Specify protocol options for opened segments",
+        OFFSET(protocol_opts), AV_OPT_TYPE_DICT,
+        .flags = AV_OPT_FLAG_DECODING_PARAM },
+    { NULL }
 };
 
 static const AVClass dash_class = {
@@ -2407,5 +3157,6 @@  AVInputFormat ff_dash_demuxer = {
     .read_packet    = dash_read_packet,
     .read_close     = dash_close,
     .read_seek      = dash_read_seek,
+    .extensions     = "mpd",
     .flags          = AVFMT_NO_BYTE_SEEK,
 };
diff --git a/libavformat/internal.h b/libavformat/internal.h
index a698761..4cccaf7 100644
--- a/libavformat/internal.h
+++ b/libavformat/internal.h
@@ -33,6 +33,8 @@ 
 #define PROBE_BUF_MIN 2048
 #define PROBE_BUF_MAX (1 << 20)
 
+#define UUID_BUF_SIZE 36
+
 #ifdef DEBUG
 #    define hex_dump_debug(class, buf, size) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size)
 #else
@@ -390,6 +392,18 @@  do {\
  */
 int ff_mkdir_p(const char *path);
 
+char *ff_uuid_to_hex(char *buff, const uint8_t *src, int lowercase);
+
+/**
+ * Parse an UUID string.
+ *
+ * @param data the parsed data is written to this pointer
+ * @param p the string to parse
+ * @return the number of bytes written that is always 16 or negative number on
+ * error
+ */
+int ff_uuid_to_data(uint8_t *data, const char *p);
+
 char *ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase);
 
 /**
@@ -927,6 +941,19 @@  int ff_unlock_avformat(void);
  */
 void ff_format_set_url(AVFormatContext *s, char *url);
 
+/*
+ * Set parent for subdemuxer opened s context. Also inherit some basic
+ * properties.
+ */
+void ff_format_set_parent(AVFormatContext *s, AVFormatContext *parent);
+
+/**
+ * Get the AVFormatContext that this context originates from. This context
+ * usually the one that was explicitly created by the user so it is useful for
+ * callbacks that would like to refer that specific context.
+ */
+AVFormatContext *ff_format_get_origin(AVFormatContext *s);
+
 void avpriv_register_devices(const AVOutputFormat * const o[], const AVInputFormat * const i[]);
 
 #endif /* AVFORMAT_INTERNAL_H */
diff --git a/libavformat/utils.c b/libavformat/utils.c
index d9971d7..d43f277 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -4947,6 +4947,53 @@  int ff_mkdir_p(const char *path)
     return ret;
 }
 
+char *ff_uuid_to_hex(char *buff, const uint8_t *src, int lowercase)
+{
+    ff_data_to_hex(buff + 0, src + 0, 4, lowercase);
+    buff[8] = '-';
+    ff_data_to_hex(buff + 9, src + 4, 2, lowercase);
+    buff[13] = '-';
+    ff_data_to_hex(buff + 14, src + 6, 2, lowercase);
+    buff[18] = '-';
+    ff_data_to_hex(buff + 19, src + 8, 2, lowercase);
+    buff[23] = '-';
+    ff_data_to_hex(buff + 24, src + 10, 6, lowercase);
+
+    return buff;
+}
+
+int ff_uuid_to_data(uint8_t *data, const char *p)
+{
+    uint8_t len;
+
+    for (len = 0; len < 16; ) {
+        uint8_t h, l;
+
+#define PARSE_XDIGIT(ch, res) \
+        if ('0' <= ch && ch <= '9') \
+            res = ch - '0'; \
+        else if ('A' <= ch && ch <= 'F') \
+            res = ch - 'A' + 10; \
+        else if ('a' <= ch && ch <= 'f') \
+            res = ch - 'a' + 10; \
+        else \
+            return -1;
+
+        PARSE_XDIGIT(p[0], h);
+        PARSE_XDIGIT(p[1], l);
+        p += 2;
+
+#undef PARSE_XDIGIT
+
+        data[len++] = (h << 4) | l;
+
+        if ((4 == len || 6 == len || 8 == len || 10 == len) && *p++ != '-')
+            return -1;
+    }
+
+    return *p == '\0' ? 16 : -1;
+}
+
 char *ff_data_to_hex(char *buff, const uint8_t *src, int s, int lowercase)
 {
     int i;