[FFmpeg-devel] avformat/ifv: added support for ifv cctv files

Submitted by swarajhota353@gmail.com on April 20, 2019, 12:14 a.m.

Details

Message ID 20190420001439.25448-1-swarajhota353@gmail.com
State New
Headers show

Commit Message

swarajhota353@gmail.com April 20, 2019, 12:14 a.m.
Fixes ticket #2956.

Signed-off-by: Swaraj Hota <swarajhota353@gmail.com>
---
I have tested it on all the samples provided in the ticket and
it works for all of them.

Please comment.
---
 Changelog                |   1 +
 libavformat/Makefile     |   1 +
 libavformat/allformats.c |   1 +
 libavformat/ifv.c        | 332 +++++++++++++++++++++++++++++++++++++++
 libavformat/version.h    |   4 +-
 5 files changed, 337 insertions(+), 2 deletions(-)
 create mode 100644 libavformat/ifv.c

--
2.21.0

Comments

swarajhota353@gmail.com April 26, 2019, 5:58 p.m.
On Sat, Apr 20, 2019 at 05:44:40AM +0530, Swaraj Hota wrote:
> Fixes ticket #2956.
> 
> Signed-off-by: Swaraj Hota <swarajhota353@gmail.com>
> ---
> I have tested it on all the samples provided in the ticket and
> it works for all of them.
> 
> Please comment.
> ---
>  Changelog                |   1 +
>  libavformat/Makefile     |   1 +
>  libavformat/allformats.c |   1 +
>  libavformat/ifv.c        | 332 +++++++++++++++++++++++++++++++++++++++
>  libavformat/version.h    |   4 +-
>  5 files changed, 337 insertions(+), 2 deletions(-)
>  create mode 100644 libavformat/ifv.c
> 
> diff --git a/Changelog b/Changelog
> index 5b2b1e5af4..2a48c6b284 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -24,6 +24,7 @@ version <next>:
>  - KUX demuxer
>  - AV1 frame split bitstream filter
>  - lscr decoder
> +- IFV demuxer
> 
> 
>  version 4.1:
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index 99be60d184..f68d41e4a5 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -231,6 +231,7 @@ OBJS-$(CONFIG_ICO_MUXER)                 += icoenc.o
>  OBJS-$(CONFIG_IDCIN_DEMUXER)             += idcin.o
>  OBJS-$(CONFIG_IDF_DEMUXER)               += bintext.o sauce.o
>  OBJS-$(CONFIG_IFF_DEMUXER)               += iff.o
> +OBJS-$(CONFIG_IFV_DEMUXER)               += ifv.o
>  OBJS-$(CONFIG_ILBC_DEMUXER)              += ilbc.o
>  OBJS-$(CONFIG_ILBC_MUXER)                += ilbc.o
>  OBJS-$(CONFIG_IMAGE2_DEMUXER)            += img2dec.o img2.o
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index d316a0529a..cd00834807 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -188,6 +188,7 @@ extern AVOutputFormat ff_ico_muxer;
>  extern AVInputFormat  ff_idcin_demuxer;
>  extern AVInputFormat  ff_idf_demuxer;
>  extern AVInputFormat  ff_iff_demuxer;
> +extern AVInputFormat  ff_ifv_demuxer;
>  extern AVInputFormat  ff_ilbc_demuxer;
>  extern AVOutputFormat ff_ilbc_muxer;
>  extern AVInputFormat  ff_image2_demuxer;
> diff --git a/libavformat/ifv.c b/libavformat/ifv.c
> new file mode 100644
> index 0000000000..dc871c5b44
> --- /dev/null
> +++ b/libavformat/ifv.c
> @@ -0,0 +1,332 @@
> +/*
> + * IFV demuxer
> + *
> + * Copyright (c) 2018 Swaraj Hota
> + *
> + * This file is part of FFmpeg.
> + *
> + * FFmpeg is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * FFmpeg is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with FFmpeg; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#include "avformat.h"
> +#include "internal.h"
> +#include "avio_internal.h"
> +
> +#define IFV_MAGIC "\x11\xd2\xd3\xab\xba\xa9\xcf\x11\
> +\x8e\xe6\x00\xc0\x0c\x20\x53\x65\x44"
> +
> +typedef struct IFVIndexEntry {
> +    uint32_t frame_offset;
> +    uint32_t frame_size;
> +    enum AVMediaType frame_type;
> +} IFVIndexEntry;
> +
> +typedef struct IFVContext {
> +    IFVIndexEntry *vid_index;
> +    IFVIndexEntry *aud_index;
> +    uint32_t index_pos;
> +    uint32_t total_vframes;
> +    uint32_t total_aframes;
> +
> +    int frame_rate;
> +    int is_audio_present;
> +    int sample_rate;
> +
> +    int video_stream_index;
> +    int audio_stream_index;
> +} IFVContext;
> +
> +static int ifv_probe(const AVProbeData *p)
> +{
> +    if (!memcmp(p->buf, IFV_MAGIC, 17))
> +        return AVPROBE_SCORE_MAX;
> +    return 0;
> +}
> +
> +static int read_next_index_entry(AVFormatContext *s, enum AVMediaType frame_type)
> +{
> +    IFVContext *ifv = s->priv_data;
> +    IFVIndexEntry *e;
> +
> +    if (frame_type == AVMEDIA_TYPE_VIDEO) {
> +        if (ifv->index_pos >= ifv->total_vframes)
> +            return 0;
> +
> +        e = &ifv->vid_index[ifv->index_pos++];
> +
> +        e->frame_offset = avio_rl32(s->pb);
> +        e->frame_size = avio_rl32(s->pb);
> +        e->frame_type = frame_type;
> +
> +        avio_skip(s->pb, 20);
> +
> +    } else if (frame_type == AVMEDIA_TYPE_AUDIO) {
> +        if (ifv->index_pos >= ifv->total_aframes)
> +            return 0;
> +
> +        e = &ifv->aud_index[ifv->index_pos++];
> +
> +        e->frame_offset = avio_rl32(s->pb);
> +        e->frame_size = avio_rl32(s->pb);
> +        e->frame_type = frame_type;
> +
> +        avio_skip(s->pb, 16);
> +    }
> +
> +    return 1;
> +}
> +
> +static int read_index(AVFormatContext *s, enum AVMediaType frame_type)
> +{
> +    IFVContext *ifv = s->priv_data;
> +    int ret;
> +
> +    if (frame_type == AVMEDIA_TYPE_VIDEO) {
> +        ret = av_reallocp_array(&ifv->vid_index, ifv->total_vframes, sizeof(IFVIndexEntry));
> +        if (ret < 0)
> +            return ret;
> +
> +    } else if (frame_type == AVMEDIA_TYPE_AUDIO) {
> +        ret = av_reallocp_array(&ifv->aud_index, ifv->total_aframes, sizeof(IFVIndexEntry));
> +        if (ret < 0)
> +            return ret;
> +    }
> +
> +    while (read_next_index_entry(s, frame_type))
> +        ;
> +
> +    return 0;
> +}
> +
> +static int parse_header(AVFormatContext *s)
> +{
> +    IFVContext *ifv = s->priv_data;
> +    uint32_t aud_magic;
> +    uint32_t vid_magic;
> +
> +    avio_skip(s->pb, 0x68);
> +    vid_magic = avio_rl32(s->pb);
> +
> +    if (vid_magic != MKTAG('H','2','6','4'))
> +        avpriv_request_sample(s, "Unknown video codec %x\n", vid_magic);
> +
> +    avio_skip(s->pb, 0x8);
> +    ifv->frame_rate = avio_rl32(s->pb);
> +
> +    avio_skip(s->pb, 0x20);
> +    ifv->sample_rate = avio_rl32(s->pb);
> +    aud_magic = avio_rl32(s->pb);
> +
> +    if (aud_magic == MKTAG('G','R','A','W')) {
> +        ifv->is_audio_present = 1;
> +    } else if (aud_magic == MKTAG('P','C','M','U')) {
> +        ifv->is_audio_present = 0;
> +    } else {
> +        avpriv_request_sample(s, "Unknown audio codec %x\n", aud_magic);
> +    }
> +
> +
> +    avio_skip(s->pb, 0x44);
> +    ifv->total_vframes = avio_rl32(s->pb);
> +    ifv->total_aframes = avio_rl32(s->pb);
> +
> +    return 0;
> +}
> +
> +static int ifv_read_header(AVFormatContext *s)
> +{
> +    IFVContext *ifv = s->priv_data;
> +    AVStream *st;
> +    int ret;
> +
> +    ret = parse_header(s);
> +    if (ret < 0)
> +        return ret;
> +
> +    ifv->vid_index = NULL;
> +    ifv->aud_index = NULL;
> +
> +    /*read video index*/
> +    avio_seek(s->pb, 0xf8, SEEK_SET);
> +
> +    ifv->index_pos = 0;
> +    ret = read_index(s, AVMEDIA_TYPE_VIDEO);
> +    if (ret < 0)
> +        return ret;
> +
> +    if (ifv->is_audio_present) {
> +        /*read audio index*/
> +        avio_seek(s->pb, 0x14918, SEEK_SET);
> +
> +        ifv->index_pos = 0;
> +        ret = read_index(s, AVMEDIA_TYPE_AUDIO);
> +        if (ret < 0)
> +            return ret;
> +    }
> +
> +
> +    st = avformat_new_stream(s, NULL);
> +
> +    if (!st)
> +        return AVERROR(ENOMEM);
> +
> +    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
> +    st->codecpar->codec_id = AV_CODEC_ID_H264;
> +    ifv->video_stream_index = st->index;
> +
> +    avpriv_set_pts_info(st, 32, 1, ifv->frame_rate);
> +
> +    if (ifv->is_audio_present) {
> +        st = avformat_new_stream(s, NULL);
> +
> +        if (!st)
> +            return AVERROR(ENOMEM);
> +
> +        st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
> +        st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
> +        st->codecpar->channels = 1;
> +        st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
> +        st->codecpar->sample_rate = ifv->sample_rate;
> +        ifv->audio_stream_index = st->index;
> +    }
> +
> +    avio_skip(s->pb, ifv->vid_index->frame_offset - avio_tell(s->pb));
> +
> +    return 0;
> +}
> +
> +static int ifv_read_packet(AVFormatContext *s, AVPacket *pkt)
> +{
> +    IFVContext *ifv = s->priv_data;
> +    IFVIndexEntry *e;
> +    uint32_t pos, nb_new_vframes, nb_new_aframes, new_index_start;
> +    int ret, i, j, vdiff, adiff;
> +
> +    vdiff = adiff = INT_MAX;
> +
> +    pos = avio_tell(s->pb);
> +
> +    for (i = 0; i < ifv->total_vframes; i++) {
> +        e = &ifv->vid_index[i];
> +        if (e->frame_offset >= pos)
> +            break;
> +    }
> +
> +    vdiff = e->frame_offset - pos;
> +
> +    if (ifv->is_audio_present && vdiff) {
> +        for (j = 0; j < ifv->total_aframes; j++) {
> +            e = &ifv->aud_index[j];
> +            if (e->frame_offset >= pos)
> +                break;
> +        }
> +
> +        adiff = e->frame_offset - pos;
> +    }
> +
> +    if (vdiff >= 0 && adiff >= 0) {
> +        /*skip to the boundary of next frame if needed*/
> +        avio_skip(s->pb, FFMIN(vdiff, adiff));
> +        if (vdiff && adiff)
> +            return 0;
> +    }
> +
> +    if (i == ifv->total_vframes) {
> +        if (ifv->is_audio_present && j == ifv->total_aframes) {
> +            /*read new video and audio indexes*/
> +
> +            avio_skip(s->pb, 0x1c);
> +            nb_new_vframes = avio_rl32(s->pb);
> +            nb_new_aframes = avio_rl32(s->pb);
> +            avio_skip(s->pb, 0xc);
> +
> +            if (avio_feof(s->pb))
> +                return AVERROR_EOF;
> +
> +            ifv->index_pos = new_index_start = ifv->total_vframes;
> +            ifv->total_vframes += nb_new_vframes;
> +
> +            ret = read_index(s, AVMEDIA_TYPE_VIDEO);
> +            if (ret < 0)
> +                return ret;
> +
> +            ifv->index_pos = ifv->total_aframes;
> +            ifv->total_aframes += nb_new_aframes;
> +
> +            ret = read_index(s, AVMEDIA_TYPE_AUDIO);
> +            if (ret < 0)
> +                return ret;
> +
> +            pos = avio_tell(s->pb);
> +            avio_skip(s->pb, ifv->vid_index[new_index_start].frame_offset - pos);
> +
> +            return 0;
> +
> +        } else if (!ifv->is_audio_present) {
> +            /*read new video index*/
> +
> +            avio_skip(s->pb, 0x1c);
> +            nb_new_vframes = avio_rl32(s->pb);
> +            avio_skip(s->pb, 0x10);
> +
> +            if (avio_feof(s->pb))
> +                return AVERROR_EOF;
> +
> +            ifv->index_pos = new_index_start = ifv->total_vframes;
> +            ifv->total_vframes += nb_new_vframes;
> +
> +            ret = read_index(s, AVMEDIA_TYPE_VIDEO);
> +            if (ret < 0)
> +                return ret;
> +
> +            pos = avio_tell(s->pb);
> +            avio_skip(s->pb, ifv->vid_index[new_index_start].frame_offset - pos);
> +
> +            return 0;
> +        }
> +    }
> +
> +    ret = av_get_packet(s->pb, pkt, e->frame_size);
> +    if (ret < 0)
> +        return ret;
> +
> +    pkt->stream_index = e->frame_type == AVMEDIA_TYPE_VIDEO?
> +                        ifv->video_stream_index: ifv->audio_stream_index;
> +
> +    return ret;
> +}
> +
> +static int ifv_read_close(AVFormatContext *s)
> +{
> +    IFVContext *ifv = s->priv_data;
> +
> +    av_freep(&ifv->vid_index);
> +    if (ifv->is_audio_present)
> +        av_freep(&ifv->aud_index);
> +
> +    return 0;
> +}
> +
> +AVInputFormat ff_ifv_demuxer = {
> +    .name           = "ifv",
> +    .long_name      = NULL_IF_CONFIG_SMALL("IFV CCTV DVR"),
> +    .priv_data_size = sizeof(IFVContext),
> +    .extensions     = "ifv",
> +    .read_probe     = ifv_probe,
> +    .read_header    = ifv_read_header,
> +    .read_packet    = ifv_read_packet,
> +    .read_close     = ifv_read_close,
> +    .flags          = AVFMT_NOTIMESTAMPS | AVFMT_NODIMENSIONS,
> +};
> diff --git a/libavformat/version.h b/libavformat/version.h
> index d57c151554..52dd95f5c6 100644
> --- a/libavformat/version.h
> +++ b/libavformat/version.h
> @@ -32,8 +32,8 @@
>  // Major bumping may affect Ticket5467, 5421, 5451(compatibility with Chromium)
>  // Also please add any ticket numbers that you believe might be affected here
>  #define LIBAVFORMAT_VERSION_MAJOR  58
> -#define LIBAVFORMAT_VERSION_MINOR  27
> -#define LIBAVFORMAT_VERSION_MICRO 102
> +#define LIBAVFORMAT_VERSION_MINOR  28
> +#define LIBAVFORMAT_VERSION_MICRO 100
> 
>  #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
>                                                 LIBAVFORMAT_VERSION_MINOR, \
> --
> 2.21.0

Ping. Please comment.
Paul B Mahol April 27, 2019, 10:16 a.m.
On 4/20/19, Swaraj Hota <swarajhota353@gmail.com> wrote:
> Fixes ticket #2956.
>
> Signed-off-by: Swaraj Hota <swarajhota353@gmail.com>
> ---
> I have tested it on all the samples provided in the ticket and
> it works for all of them.
>
> Please comment.
> ---
>  Changelog                |   1 +
>  libavformat/Makefile     |   1 +
>  libavformat/allformats.c |   1 +
>  libavformat/ifv.c        | 332 +++++++++++++++++++++++++++++++++++++++
>  libavformat/version.h    |   4 +-
>  5 files changed, 337 insertions(+), 2 deletions(-)
>  create mode 100644 libavformat/ifv.c
>

Generally it is fine. The only issue may be those hardcoded offsets.

Patch hide | download patch | download mbox

diff --git a/Changelog b/Changelog
index 5b2b1e5af4..2a48c6b284 100644
--- a/Changelog
+++ b/Changelog
@@ -24,6 +24,7 @@  version <next>:
 - KUX demuxer
 - AV1 frame split bitstream filter
 - lscr decoder
+- IFV demuxer


 version 4.1:
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 99be60d184..f68d41e4a5 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -231,6 +231,7 @@  OBJS-$(CONFIG_ICO_MUXER)                 += icoenc.o
 OBJS-$(CONFIG_IDCIN_DEMUXER)             += idcin.o
 OBJS-$(CONFIG_IDF_DEMUXER)               += bintext.o sauce.o
 OBJS-$(CONFIG_IFF_DEMUXER)               += iff.o
+OBJS-$(CONFIG_IFV_DEMUXER)               += ifv.o
 OBJS-$(CONFIG_ILBC_DEMUXER)              += ilbc.o
 OBJS-$(CONFIG_ILBC_MUXER)                += ilbc.o
 OBJS-$(CONFIG_IMAGE2_DEMUXER)            += img2dec.o img2.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index d316a0529a..cd00834807 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -188,6 +188,7 @@  extern AVOutputFormat ff_ico_muxer;
 extern AVInputFormat  ff_idcin_demuxer;
 extern AVInputFormat  ff_idf_demuxer;
 extern AVInputFormat  ff_iff_demuxer;
+extern AVInputFormat  ff_ifv_demuxer;
 extern AVInputFormat  ff_ilbc_demuxer;
 extern AVOutputFormat ff_ilbc_muxer;
 extern AVInputFormat  ff_image2_demuxer;
diff --git a/libavformat/ifv.c b/libavformat/ifv.c
new file mode 100644
index 0000000000..dc871c5b44
--- /dev/null
+++ b/libavformat/ifv.c
@@ -0,0 +1,332 @@ 
+/*
+ * IFV demuxer
+ *
+ * Copyright (c) 2018 Swaraj Hota
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "internal.h"
+#include "avio_internal.h"
+
+#define IFV_MAGIC "\x11\xd2\xd3\xab\xba\xa9\xcf\x11\
+\x8e\xe6\x00\xc0\x0c\x20\x53\x65\x44"
+
+typedef struct IFVIndexEntry {
+    uint32_t frame_offset;
+    uint32_t frame_size;
+    enum AVMediaType frame_type;
+} IFVIndexEntry;
+
+typedef struct IFVContext {
+    IFVIndexEntry *vid_index;
+    IFVIndexEntry *aud_index;
+    uint32_t index_pos;
+    uint32_t total_vframes;
+    uint32_t total_aframes;
+
+    int frame_rate;
+    int is_audio_present;
+    int sample_rate;
+
+    int video_stream_index;
+    int audio_stream_index;
+} IFVContext;
+
+static int ifv_probe(const AVProbeData *p)
+{
+    if (!memcmp(p->buf, IFV_MAGIC, 17))
+        return AVPROBE_SCORE_MAX;
+    return 0;
+}
+
+static int read_next_index_entry(AVFormatContext *s, enum AVMediaType frame_type)
+{
+    IFVContext *ifv = s->priv_data;
+    IFVIndexEntry *e;
+
+    if (frame_type == AVMEDIA_TYPE_VIDEO) {
+        if (ifv->index_pos >= ifv->total_vframes)
+            return 0;
+
+        e = &ifv->vid_index[ifv->index_pos++];
+
+        e->frame_offset = avio_rl32(s->pb);
+        e->frame_size = avio_rl32(s->pb);
+        e->frame_type = frame_type;
+
+        avio_skip(s->pb, 20);
+
+    } else if (frame_type == AVMEDIA_TYPE_AUDIO) {
+        if (ifv->index_pos >= ifv->total_aframes)
+            return 0;
+
+        e = &ifv->aud_index[ifv->index_pos++];
+
+        e->frame_offset = avio_rl32(s->pb);
+        e->frame_size = avio_rl32(s->pb);
+        e->frame_type = frame_type;
+
+        avio_skip(s->pb, 16);
+    }
+
+    return 1;
+}
+
+static int read_index(AVFormatContext *s, enum AVMediaType frame_type)
+{
+    IFVContext *ifv = s->priv_data;
+    int ret;
+
+    if (frame_type == AVMEDIA_TYPE_VIDEO) {
+        ret = av_reallocp_array(&ifv->vid_index, ifv->total_vframes, sizeof(IFVIndexEntry));
+        if (ret < 0)
+            return ret;
+
+    } else if (frame_type == AVMEDIA_TYPE_AUDIO) {
+        ret = av_reallocp_array(&ifv->aud_index, ifv->total_aframes, sizeof(IFVIndexEntry));
+        if (ret < 0)
+            return ret;
+    }
+
+    while (read_next_index_entry(s, frame_type))
+        ;
+
+    return 0;
+}
+
+static int parse_header(AVFormatContext *s)
+{
+    IFVContext *ifv = s->priv_data;
+    uint32_t aud_magic;
+    uint32_t vid_magic;
+
+    avio_skip(s->pb, 0x68);
+    vid_magic = avio_rl32(s->pb);
+
+    if (vid_magic != MKTAG('H','2','6','4'))
+        avpriv_request_sample(s, "Unknown video codec %x\n", vid_magic);
+
+    avio_skip(s->pb, 0x8);
+    ifv->frame_rate = avio_rl32(s->pb);
+
+    avio_skip(s->pb, 0x20);
+    ifv->sample_rate = avio_rl32(s->pb);
+    aud_magic = avio_rl32(s->pb);
+
+    if (aud_magic == MKTAG('G','R','A','W')) {
+        ifv->is_audio_present = 1;
+    } else if (aud_magic == MKTAG('P','C','M','U')) {
+        ifv->is_audio_present = 0;
+    } else {
+        avpriv_request_sample(s, "Unknown audio codec %x\n", aud_magic);
+    }
+
+
+    avio_skip(s->pb, 0x44);
+    ifv->total_vframes = avio_rl32(s->pb);
+    ifv->total_aframes = avio_rl32(s->pb);
+
+    return 0;
+}
+
+static int ifv_read_header(AVFormatContext *s)
+{
+    IFVContext *ifv = s->priv_data;
+    AVStream *st;
+    int ret;
+
+    ret = parse_header(s);
+    if (ret < 0)
+        return ret;
+
+    ifv->vid_index = NULL;
+    ifv->aud_index = NULL;
+
+    /*read video index*/
+    avio_seek(s->pb, 0xf8, SEEK_SET);
+
+    ifv->index_pos = 0;
+    ret = read_index(s, AVMEDIA_TYPE_VIDEO);
+    if (ret < 0)
+        return ret;
+
+    if (ifv->is_audio_present) {
+        /*read audio index*/
+        avio_seek(s->pb, 0x14918, SEEK_SET);
+
+        ifv->index_pos = 0;
+        ret = read_index(s, AVMEDIA_TYPE_AUDIO);
+        if (ret < 0)
+            return ret;
+    }
+
+
+    st = avformat_new_stream(s, NULL);
+
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+    st->codecpar->codec_id = AV_CODEC_ID_H264;
+    ifv->video_stream_index = st->index;
+
+    avpriv_set_pts_info(st, 32, 1, ifv->frame_rate);
+
+    if (ifv->is_audio_present) {
+        st = avformat_new_stream(s, NULL);
+
+        if (!st)
+            return AVERROR(ENOMEM);
+
+        st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
+        st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
+        st->codecpar->channels = 1;
+        st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
+        st->codecpar->sample_rate = ifv->sample_rate;
+        ifv->audio_stream_index = st->index;
+    }
+
+    avio_skip(s->pb, ifv->vid_index->frame_offset - avio_tell(s->pb));
+
+    return 0;
+}
+
+static int ifv_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    IFVContext *ifv = s->priv_data;
+    IFVIndexEntry *e;
+    uint32_t pos, nb_new_vframes, nb_new_aframes, new_index_start;
+    int ret, i, j, vdiff, adiff;
+
+    vdiff = adiff = INT_MAX;
+
+    pos = avio_tell(s->pb);
+
+    for (i = 0; i < ifv->total_vframes; i++) {
+        e = &ifv->vid_index[i];
+        if (e->frame_offset >= pos)
+            break;
+    }
+
+    vdiff = e->frame_offset - pos;
+
+    if (ifv->is_audio_present && vdiff) {
+        for (j = 0; j < ifv->total_aframes; j++) {
+            e = &ifv->aud_index[j];
+            if (e->frame_offset >= pos)
+                break;
+        }
+
+        adiff = e->frame_offset - pos;
+    }
+
+    if (vdiff >= 0 && adiff >= 0) {
+        /*skip to the boundary of next frame if needed*/
+        avio_skip(s->pb, FFMIN(vdiff, adiff));
+        if (vdiff && adiff)
+            return 0;
+    }
+
+    if (i == ifv->total_vframes) {
+        if (ifv->is_audio_present && j == ifv->total_aframes) {
+            /*read new video and audio indexes*/
+
+            avio_skip(s->pb, 0x1c);
+            nb_new_vframes = avio_rl32(s->pb);
+            nb_new_aframes = avio_rl32(s->pb);
+            avio_skip(s->pb, 0xc);
+
+            if (avio_feof(s->pb))
+                return AVERROR_EOF;
+
+            ifv->index_pos = new_index_start = ifv->total_vframes;
+            ifv->total_vframes += nb_new_vframes;
+
+            ret = read_index(s, AVMEDIA_TYPE_VIDEO);
+            if (ret < 0)
+                return ret;
+
+            ifv->index_pos = ifv->total_aframes;
+            ifv->total_aframes += nb_new_aframes;
+
+            ret = read_index(s, AVMEDIA_TYPE_AUDIO);
+            if (ret < 0)
+                return ret;
+
+            pos = avio_tell(s->pb);
+            avio_skip(s->pb, ifv->vid_index[new_index_start].frame_offset - pos);
+
+            return 0;
+
+        } else if (!ifv->is_audio_present) {
+            /*read new video index*/
+
+            avio_skip(s->pb, 0x1c);
+            nb_new_vframes = avio_rl32(s->pb);
+            avio_skip(s->pb, 0x10);
+
+            if (avio_feof(s->pb))
+                return AVERROR_EOF;
+
+            ifv->index_pos = new_index_start = ifv->total_vframes;
+            ifv->total_vframes += nb_new_vframes;
+
+            ret = read_index(s, AVMEDIA_TYPE_VIDEO);
+            if (ret < 0)
+                return ret;
+
+            pos = avio_tell(s->pb);
+            avio_skip(s->pb, ifv->vid_index[new_index_start].frame_offset - pos);
+
+            return 0;
+        }
+    }
+
+    ret = av_get_packet(s->pb, pkt, e->frame_size);
+    if (ret < 0)
+        return ret;
+
+    pkt->stream_index = e->frame_type == AVMEDIA_TYPE_VIDEO?
+                        ifv->video_stream_index: ifv->audio_stream_index;
+
+    return ret;
+}
+
+static int ifv_read_close(AVFormatContext *s)
+{
+    IFVContext *ifv = s->priv_data;
+
+    av_freep(&ifv->vid_index);
+    if (ifv->is_audio_present)
+        av_freep(&ifv->aud_index);
+
+    return 0;
+}
+
+AVInputFormat ff_ifv_demuxer = {
+    .name           = "ifv",
+    .long_name      = NULL_IF_CONFIG_SMALL("IFV CCTV DVR"),
+    .priv_data_size = sizeof(IFVContext),
+    .extensions     = "ifv",
+    .read_probe     = ifv_probe,
+    .read_header    = ifv_read_header,
+    .read_packet    = ifv_read_packet,
+    .read_close     = ifv_read_close,
+    .flags          = AVFMT_NOTIMESTAMPS | AVFMT_NODIMENSIONS,
+};
diff --git a/libavformat/version.h b/libavformat/version.h
index d57c151554..52dd95f5c6 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -32,8 +32,8 @@ 
 // Major bumping may affect Ticket5467, 5421, 5451(compatibility with Chromium)
 // Also please add any ticket numbers that you believe might be affected here
 #define LIBAVFORMAT_VERSION_MAJOR  58
-#define LIBAVFORMAT_VERSION_MINOR  27
-#define LIBAVFORMAT_VERSION_MICRO 102
+#define LIBAVFORMAT_VERSION_MINOR  28
+#define LIBAVFORMAT_VERSION_MICRO 100

 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \