In many older QuickTime files, the audio format, or "fourcc", is
0x00000000. The QuickTime File Format Specification states the following
regarding this situation:
"This format descriptor should not be used, but may be found in some
files. Samples are assumed to be stored in either 'raw ' or 'twos'
format, depending on the sample size field in the sound description."
MPlayer handles this logic by itself, but FFmpeg/FFplay currently does
not.
Mats
--
Mats Peterson
http://matsp888.no-ip.org/~mats/
>From d8507d9b0645585d2d27c614f1f7d3347edf8733 Mon Sep 17 00:00:00 2001
From: Mats Peterson <matsp...@yahoo.com>
Date: Fri, 8 Jan 2016 12:55:59 +0100
Subject: [PATCH v6] lavf/matroskadec: A_QUICKTIME and fourcc 0x00000000
In many older QuickTime files, the audio format, or "fourcc", is
0x00000000. The QuickTime File Format Specification states the following
regarding this situation:
"This format descriptor should not be used, but may be found in some
files. Samples are assumed to be stored in either 'raw ' or 'twos'
format, depending on the sample size field in the sound description."
MPlayer handles this logic by itself, but FFmpeg/FFplay currently does
not.
Mats
---
libavformat/matroskadec.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
index 9de7cfb..ea68c6a 100644
--- a/libavformat/matroskadec.c
+++ b/libavformat/matroskadec.c
@@ -1869,6 +1869,15 @@ static int matroska_parse_tracks(AVFormatContext *s)
fourcc = AV_RL32(track->codec_priv.data);
codec_id = ff_codec_get_id(ff_codec_movaudio_tags, fourcc);
}
+ if (fourcc == 0) {
+ if (track->audio.bitdepth == 8) {
+ fourcc = MKTAG('r','a','w',' ');
+ codec_id = ff_codec_get_id(ff_codec_movaudio_tags, fourcc);
+ } else if (track->audio.bitdepth == 16) {
+ fourcc = MKTAG('t','w','o','s');
+ codec_id = ff_codec_get_id(ff_codec_movaudio_tags, fourcc);
+ }
+ }
} else if (!strcmp(track->codec_id, "V_QUICKTIME") &&
(track->codec_priv.size >= 21) &&
(track->codec_priv.data)) {
--
1.7.10.4
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
