diff mbox series

[FFmpeg-devel,v2] avformat/dhav: also support ZLAV packets

Message ID 20201108094143.345676-1-mike@keeley.net.nz
State New
Headers show
Series [FFmpeg-devel,v2] avformat/dhav: also support ZLAV packets
Related show

Checks

Context Check Description
andriy/x86_make success Make finished
andriy/x86_make_fate success Make fate finished
andriy/PPC64_make success Make finished
andriy/PPC64_make_fate success Make fate finished

Commit Message

Michael Keeley Nov. 8, 2020, 9:41 a.m. UTC
Some DVRs (e.g. D7008FH made by iSmart Cities (Zhuhai) Limited) output the same format .dav file,
but use ZLAV/zlav tags to delimit the packets instead of DHAV/dhav.

Signed-off-by: Michael Keeley <mike@keeley.net.nz>
---
 Changelog             |  1 +
 libavformat/dhav.c    | 31 ++++++++++++++++++++++---------
 libavformat/version.h |  2 +-
 3 files changed, 24 insertions(+), 10 deletions(-)

Comments

Michael Keeley Nov. 14, 2020, 12:09 p.m. UTC | #1
Ping :-)

> -----Original Message-----
> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces@ffmpeg.org] On Behalf
> Of Michael Keeley
> Sent: Sunday, 8 November 2020 10:42 pm
> To: ffmpeg-devel@ffmpeg.org
> Cc: Michael Keeley
> Subject: [FFmpeg-devel] [PATCH v2] avformat/dhav: also support ZLAV
> packets
> 
> Some DVRs (e.g. D7008FH made by iSmart Cities (Zhuhai) Limited) output
> the same format .dav file,
> but use ZLAV/zlav tags to delimit the packets instead of DHAV/dhav.
> 
> Signed-off-by: Michael Keeley <mike@keeley.net.nz>
> ---
>  Changelog             |  1 +
>  libavformat/dhav.c    | 31 ++++++++++++++++++++++---------
>  libavformat/version.h |  2 +-
>  3 files changed, 24 insertions(+), 10 deletions(-)
> 
> diff --git a/Changelog b/Changelog
> index 0ea1901bbe..a56216543d 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -41,6 +41,7 @@ version <next>:
>  - LEGO Racers ALP (.tun & .pcm) muxer
>  - AV1 VAAPI decoder
>  - adenorm filter
> +- Add ZLAV format to DHAV demuxer
> 
> 
>  version 4.3:
> diff --git a/libavformat/dhav.c b/libavformat/dhav.c
> index 53deaff77e..40c2cc78b0 100644
> --- a/libavformat/dhav.c
> +++ b/libavformat/dhav.c
> @@ -1,5 +1,5 @@
>  /*
> - * DHAV demuxer
> + * DHAV/ZLAV demuxer
>   *
>   * Copyright (c) 2018 Paul B Mahol
>   *
> @@ -57,7 +57,7 @@ static int dhav_probe(const AVProbeData *p)
>      if (!memcmp(p->buf, "DAHUA", 5))
>          return AVPROBE_SCORE_MAX;
> 
> -    if (memcmp(p->buf, "DHAV", 4))
> +    if (memcmp(p->buf, "DHAV", 4) && memcmp(p->buf, "ZLAV", 4))
>          return 0;
> 
>      if (p->buf[4] == 0xf0 ||
> @@ -163,6 +163,19 @@ static int parse_ext(AVFormatContext *s, int
> length)
>      return 0;
>  }
> 
> +static int read_start_tag(AVIOContext *pb)
> +{
> +    unsigned int start_tag = avio_rl32(pb);
> +    return start_tag == MKTAG('D','H','A','V') || start_tag ==
> MKTAG('Z','L','A','V');
> +}
> +
> +static int read_end_tag(AVIOContext *pb)
> +{
> +    unsigned int end_tag = avio_rl32(pb);
> +    return end_tag == MKTAG('d','h','a','v') || end_tag ==
> MKTAG('z','l','a','v');
> +}
> +
> +
>  static int read_chunk(AVFormatContext *s)
>  {
>      DHAVContext *dhav = s->priv_data;
> @@ -173,11 +186,11 @@ static int read_chunk(AVFormatContext *s)
>      if (avio_feof(s->pb))
>          return AVERROR_EOF;
> 
> -    if (avio_rl32(s->pb) != MKTAG('D','H','A','V')) {
> +    if (!read_start_tag(s->pb)) {
>          dhav->last_good_pos += 0x8000;
>          avio_seek(s->pb, dhav->last_good_pos, SEEK_SET);
> 
> -        while (avio_rl32(s->pb) != MKTAG('D','H','A','V')) {
> +        while (!read_start_tag(s->pb)) {
>              if (avio_feof(s->pb))
>                  return AVERROR_EOF;
>              dhav->last_good_pos += 0x8000;
> @@ -247,7 +260,7 @@ static int64_t get_duration(AVFormatContext *s)
>          return 0;
> 
>      avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
> -    if (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
> +    if (read_end_tag(s->pb)) {
>          int seek_back = avio_rl32(s->pb);
> 
>          avio_seek(s->pb, -seek_back, SEEK_CUR);
> @@ -281,12 +294,12 @@ static int dhav_read_header(AVFormatContext *s)
>          avio_skip(s->pb, 0x400 - 5);
>          dhav->last_good_pos = avio_tell(s->pb);
>      } else {
> -        if (!memcmp(signature, "DHAV", 4)) {
> +        if (!memcmp(signature, "DHAV", 4) || !memcmp(signature,
> "ZLAV", 4)) {
>              avio_seek(s->pb, -5, SEEK_CUR);
>              dhav->last_good_pos = avio_tell(s->pb);
>          } else if (s->pb->seekable) {
>              avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
> -            while (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
> +            while (read_end_tag(s->pb)) {
>                  int seek_back;
> 
>                  seek_back = avio_rl32(s->pb) + 8;
> @@ -409,7 +422,7 @@ retry:
>      stream_index = dhav->type == 0xf0 ? dhav->audio_stream_index :
> dhav->video_stream_index;
>      if (stream_index < 0) {
>          avio_skip(s->pb, ret);
> -        if (avio_rl32(s->pb) == MKTAG('d','h','a','v'))
> +        if (read_end_tag(s->pb))
>              avio_skip(s->pb, 4);
>          goto retry;
>      }
> @@ -425,7 +438,7 @@ retry:
>      if (pkt->stream_index >= 0)
>          pkt->pts = get_pts(s, pkt->stream_index);
>      pkt->pos = dhav->last_good_pos;
> -    if (avio_rl32(s->pb) == MKTAG('d','h','a','v'))
> +    if (read_end_tag(s->pb))
>          avio_skip(s->pb, 4);
> 
>      return ret;
> diff --git a/libavformat/version.h b/libavformat/version.h
> index ddcca9ae50..b43193bcb1 100644
> --- a/libavformat/version.h
> +++ b/libavformat/version.h
> @@ -32,7 +32,7 @@
>  // 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  64
> +#define LIBAVFORMAT_VERSION_MINOR  65
>  #define LIBAVFORMAT_VERSION_MICRO 100
> 
>  #define LIBAVFORMAT_VERSION_INT
> AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
> --
> 2.25.1
> 
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> 
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
Zane van Iperen Nov. 14, 2020, 12:58 p.m. UTC | #2
On 8/11/20 7:41 pm, Michael Keeley wrote:
> Some DVRs (e.g. D7008FH made by iSmart Cities (Zhuhai) Limited) output the same format .dav file,
> but use ZLAV/zlav tags to delimit the packets instead of DHAV/dhav.
> 
> Signed-off-by: Michael Keeley <mike@keeley.net.nz>
> ---
>   Changelog             |  1 +
>   libavformat/dhav.c    | 31 ++++++++++++++++++++++---------
>   libavformat/version.h |  2 +-
>   3 files changed, 24 insertions(+), 10 deletions(-)
> 
> diff --git a/Changelog b/Changelog
> index 0ea1901bbe..a56216543d 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -41,6 +41,7 @@ version <next>:
>   - LEGO Racers ALP (.tun & .pcm) muxer
>   - AV1 VAAPI decoder
>   - adenorm filter
> +- Add ZLAV format to DHAV demuxer

Just make this "ZLAV demuxer" or something similar.

>   
>   
>   version 4.3:
> diff --git a/libavformat/dhav.c b/libavformat/dhav.c
> index 53deaff77e..40c2cc78b0 100644
> --- a/libavformat/dhav.c
> +++ b/libavformat/dhav.c
> @@ -1,5 +1,5 @@
>   /*
> - * DHAV demuxer
> + * DHAV/ZLAV demuxer
>    *
>    * Copyright (c) 2018 Paul B Mahol
>    *
> @@ -57,7 +57,7 @@ static int dhav_probe(const AVProbeData *p)
>       if (!memcmp(p->buf, "DAHUA", 5))
>           return AVPROBE_SCORE_MAX;
>   
> -    if (memcmp(p->buf, "DHAV", 4))
> +    if (memcmp(p->buf, "DHAV", 4) && memcmp(p->buf, "ZLAV", 4))
>           return 0;
>   
>       if (p->buf[4] == 0xf0 ||
> @@ -163,6 +163,19 @@ static int parse_ext(AVFormatContext *s, int length)
>       return 0;
>   }
>   
> +static int read_start_tag(AVIOContext *pb)
> +{
> +    unsigned int start_tag = avio_rl32(pb);
> +    return start_tag == MKTAG('D','H','A','V') || start_tag == MKTAG('Z','L','A','V');
> +}
> +
> +static int read_end_tag(AVIOContext *pb)
> +{
> +    unsigned int end_tag = avio_rl32(pb);
> +    return end_tag == MKTAG('d','h','a','v') || end_tag == MKTAG('z','l','a','v');
> +}
> +
> +
>   static int read_chunk(AVFormatContext *s)
>   {
>       DHAVContext *dhav = s->priv_data;
> @@ -173,11 +186,11 @@ static int read_chunk(AVFormatContext *s)
>       if (avio_feof(s->pb))
>           return AVERROR_EOF;
>   
> -    if (avio_rl32(s->pb) != MKTAG('D','H','A','V')) {
> +    if (!read_start_tag(s->pb)) {
>           dhav->last_good_pos += 0x8000;
>           avio_seek(s->pb, dhav->last_good_pos, SEEK_SET);
>   
> -        while (avio_rl32(s->pb) != MKTAG('D','H','A','V')) {
> +        while (!read_start_tag(s->pb)) {
>               if (avio_feof(s->pb))
>                   return AVERROR_EOF;
>               dhav->last_good_pos += 0x8000;
> @@ -247,7 +260,7 @@ static int64_t get_duration(AVFormatContext *s)
>           return 0;
>   
>       avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
> -    if (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
> +    if (read_end_tag(s->pb)) {
>           int seek_back = avio_rl32(s->pb);
>   
>           avio_seek(s->pb, -seek_back, SEEK_CUR);
> @@ -281,12 +294,12 @@ static int dhav_read_header(AVFormatContext *s)
>           avio_skip(s->pb, 0x400 - 5);
>           dhav->last_good_pos = avio_tell(s->pb);
>       } else {
> -        if (!memcmp(signature, "DHAV", 4)) {
> +        if (!memcmp(signature, "DHAV", 4) || !memcmp(signature, "ZLAV", 4)) {
>               avio_seek(s->pb, -5, SEEK_CUR);
>               dhav->last_good_pos = avio_tell(s->pb);
>           } else if (s->pb->seekable) {
>               avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
> -            while (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
> +            while (read_end_tag(s->pb)) {
>                   int seek_back;
>   
>                   seek_back = avio_rl32(s->pb) + 8;
> @@ -409,7 +422,7 @@ retry:
>       stream_index = dhav->type == 0xf0 ? dhav->audio_stream_index : dhav->video_stream_index;
>       if (stream_index < 0) {
>           avio_skip(s->pb, ret);
> -        if (avio_rl32(s->pb) == MKTAG('d','h','a','v'))
> +        if (read_end_tag(s->pb))
>               avio_skip(s->pb, 4);
>           goto retry;
>       }
> @@ -425,7 +438,7 @@ retry:
>       if (pkt->stream_index >= 0)
>           pkt->pts = get_pts(s, pkt->stream_index);
>       pkt->pos = dhav->last_good_pos;
> -    if (avio_rl32(s->pb) == MKTAG('d','h','a','v'))
> +    if (read_end_tag(s->pb))
>           avio_skip(s->pb, 4);
>   
>       return ret;
> diff --git a/libavformat/version.h b/libavformat/version.h
> index ddcca9ae50..b43193bcb1 100644
> --- a/libavformat/version.h
> +++ b/libavformat/version.h
> @@ -32,7 +32,7 @@
>   // 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  64
> +#define LIBAVFORMAT_VERSION_MINOR  65
>   #define LIBAVFORMAT_VERSION_MICRO 100
>   
>   #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
> 

This looks mostly alright to me at a glance.

One thing to note, this would accept packets starting with "DHAV" and ending
with "zlav" (and vice versa).

Could this be a problem? If so, might it be worth storing the current "type"
and ensuring you get the correct delimiter?
diff mbox series

Patch

diff --git a/Changelog b/Changelog
index 0ea1901bbe..a56216543d 100644
--- a/Changelog
+++ b/Changelog
@@ -41,6 +41,7 @@  version <next>:
 - LEGO Racers ALP (.tun & .pcm) muxer
 - AV1 VAAPI decoder
 - adenorm filter
+- Add ZLAV format to DHAV demuxer
 
 
 version 4.3:
diff --git a/libavformat/dhav.c b/libavformat/dhav.c
index 53deaff77e..40c2cc78b0 100644
--- a/libavformat/dhav.c
+++ b/libavformat/dhav.c
@@ -1,5 +1,5 @@ 
 /*
- * DHAV demuxer
+ * DHAV/ZLAV demuxer
  *
  * Copyright (c) 2018 Paul B Mahol
  *
@@ -57,7 +57,7 @@  static int dhav_probe(const AVProbeData *p)
     if (!memcmp(p->buf, "DAHUA", 5))
         return AVPROBE_SCORE_MAX;
 
-    if (memcmp(p->buf, "DHAV", 4))
+    if (memcmp(p->buf, "DHAV", 4) && memcmp(p->buf, "ZLAV", 4))
         return 0;
 
     if (p->buf[4] == 0xf0 ||
@@ -163,6 +163,19 @@  static int parse_ext(AVFormatContext *s, int length)
     return 0;
 }
 
+static int read_start_tag(AVIOContext *pb)
+{
+    unsigned int start_tag = avio_rl32(pb);
+    return start_tag == MKTAG('D','H','A','V') || start_tag == MKTAG('Z','L','A','V');
+}
+
+static int read_end_tag(AVIOContext *pb)
+{
+    unsigned int end_tag = avio_rl32(pb);
+    return end_tag == MKTAG('d','h','a','v') || end_tag == MKTAG('z','l','a','v');
+}
+
+
 static int read_chunk(AVFormatContext *s)
 {
     DHAVContext *dhav = s->priv_data;
@@ -173,11 +186,11 @@  static int read_chunk(AVFormatContext *s)
     if (avio_feof(s->pb))
         return AVERROR_EOF;
 
-    if (avio_rl32(s->pb) != MKTAG('D','H','A','V')) {
+    if (!read_start_tag(s->pb)) {
         dhav->last_good_pos += 0x8000;
         avio_seek(s->pb, dhav->last_good_pos, SEEK_SET);
 
-        while (avio_rl32(s->pb) != MKTAG('D','H','A','V')) {
+        while (!read_start_tag(s->pb)) {
             if (avio_feof(s->pb))
                 return AVERROR_EOF;
             dhav->last_good_pos += 0x8000;
@@ -247,7 +260,7 @@  static int64_t get_duration(AVFormatContext *s)
         return 0;
 
     avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
-    if (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
+    if (read_end_tag(s->pb)) {
         int seek_back = avio_rl32(s->pb);
 
         avio_seek(s->pb, -seek_back, SEEK_CUR);
@@ -281,12 +294,12 @@  static int dhav_read_header(AVFormatContext *s)
         avio_skip(s->pb, 0x400 - 5);
         dhav->last_good_pos = avio_tell(s->pb);
     } else {
-        if (!memcmp(signature, "DHAV", 4)) {
+        if (!memcmp(signature, "DHAV", 4) || !memcmp(signature, "ZLAV", 4)) {
             avio_seek(s->pb, -5, SEEK_CUR);
             dhav->last_good_pos = avio_tell(s->pb);
         } else if (s->pb->seekable) {
             avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
-            while (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
+            while (read_end_tag(s->pb)) {
                 int seek_back;
 
                 seek_back = avio_rl32(s->pb) + 8;
@@ -409,7 +422,7 @@  retry:
     stream_index = dhav->type == 0xf0 ? dhav->audio_stream_index : dhav->video_stream_index;
     if (stream_index < 0) {
         avio_skip(s->pb, ret);
-        if (avio_rl32(s->pb) == MKTAG('d','h','a','v'))
+        if (read_end_tag(s->pb))
             avio_skip(s->pb, 4);
         goto retry;
     }
@@ -425,7 +438,7 @@  retry:
     if (pkt->stream_index >= 0)
         pkt->pts = get_pts(s, pkt->stream_index);
     pkt->pos = dhav->last_good_pos;
-    if (avio_rl32(s->pb) == MKTAG('d','h','a','v'))
+    if (read_end_tag(s->pb))
         avio_skip(s->pb, 4);
 
     return ret;
diff --git a/libavformat/version.h b/libavformat/version.h
index ddcca9ae50..b43193bcb1 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -32,7 +32,7 @@ 
 // 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  64
+#define LIBAVFORMAT_VERSION_MINOR  65
 #define LIBAVFORMAT_VERSION_MICRO 100
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \