In many older QuickTime files, the audio format, or "fourcc", is
0x00000000 (AV_CODEC_ID_NONE). 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 861ecae89d3a33ae9dffa34494569fb9994071ff Mon Sep 17 00:00:00 2001
From: Mats Peterson <matsp...@yahoo.com>
Date: Mon, 4 Jan 2016 21:40:25 +0100
Subject: [PATCH] lavf/mov: Audio and AV_CODEC_ID_NONE
In many older QuickTime files, the audio format, or "fourcc", is
0x00000000 (AV_CODEC_ID_NONE). 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/mov.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 78081ce..f3ed85e 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -1899,6 +1899,17 @@ static void mov_parse_stsd_audio(MOVContext *c, AVIOContext *pb,
sc->samples_per_frame = 160;
sc->bytes_per_frame = 33;
break;
+ case AV_CODEC_ID_NONE:
+ if (st->codec->bits_per_coded_sample == 8) {
+ st->codec->codec_tag = MKTAG('r','a','w',' ');
+ st->codec->codec_id = ff_codec_get_id(ff_codec_movaudio_tags,
+ st->codec->codec_tag);
+ } else if (st->codec->bits_per_coded_sample == 16) {
+ st->codec->codec_tag = MKTAG('t','w','o','s');
+ st->codec->codec_id = ff_codec_get_id(ff_codec_movaudio_tags,
+ st->codec->codec_tag);
+ }
+ break;
default:
break;
}
--
1.7.10.4
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