[FFmpeg-trac] #1755(avformat:open): Incorrect timestamps for aac in avi (was: Audio becomes silent on some avi files. (This problem is reproduced during 1x play and seek))
FFmpeg
trac at avcodec.org
Thu Sep 20 16:22:00 CEST 2012
#1755: Incorrect timestamps for aac in avi
-------------------------------------+------------------------------------
Reporter: Heesuk Jung | Owner:
Type: defect | Status: open
Priority: normal | Component: avformat
Version: git-master | Resolution:
Keywords: avi aac pts | Blocked By:
Blocking: | Reproduced by developer: 1
Analyzed by developer: 0 |
-------------------------------------+------------------------------------
Changes (by cehoyos):
* keywords: => avi aac pts
* status: new => open
* version: 0.11.1 => git-master
* reproduced: 0 => 1
Comment:
Audio timestamps for the sample file (uploaded to samples/ffmpeg-
bugs/trac/ticket1755) are wrong with lavf, ffplay tries to correct it by
playing video too slow, leading to A/V-desync, same wrong timestamps are
shown with mplayer -demuxer lavf, the file plays fine with mplayer
-demuxer avi
{{{
$ time ffplay
016_avi_mpeg4_sp\[720\@24fps\]_aac\[2ch_128kbps_44.1khz\].avi\[MV\]_origin.avi
ffplay version N-44632-ga16c512 Copyright (c) 2003-2012 the FFmpeg
developers
built on Sep 20 2012 16:11:00 with gcc 4.5.3 (GCC)
configuration: --cc=/usr/local/gcc-4.5.3/bin/gcc --enable-gpl
libavutil 51. 73.101 / 51. 73.101
libavcodec 54. 56.100 / 54. 56.100
libavformat 54. 27.101 / 54. 27.101
libavdevice 54. 2.101 / 54. 2.101
libavfilter 3. 16.105 / 3. 16.105
libswscale 2. 1.101 / 2. 1.101
libswresample 0. 15.100 / 0. 15.100
libpostproc 52. 0.100 / 52. 0.100
[avi @ 0x151eb20] non-interleaved AVI
Input #0, avi, from
'016_avi_mpeg4_sp[720 at 24fps]_aac[2ch_128kbps_44.1khz].avi[MV]_origin.avi':
Metadata:
encoder : PotEncoder
Duration: 00:00:31.00, start: 0.000000, bitrate: 6907 kb/s
Stream #0:0: Video: mpeg4 (Simple Profile) (XVID / 0x44495658),
yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 24 tbr, 24 tbn, 24 tbc
Stream #0:1: Audio: aac ([255][0][0][0] / 0x00FF), 44100 Hz, stereo,
s16, 128 kb/s
Frame changed from size:0x0 to size:1280x720
9.98 A-V: -2.689 fd= 0 aq= 118KB vq= 233KB sq= 0B f=0/0 f=0/0
real 0m25.429s
user 0m2.105s
sys 0m0.218s
}}}
ffmpeg corrects the timestamps, resulting video seems fine afaict:
{{{
$ ffmpeg -i
016_avi_mpeg4_sp\[720\@24fps\]_aac\[2ch_128kbps_44.1khz\].avi\[MV\]_origin.avi
-qscale 2 out.avi
ffmpeg version N-44632-ga16c512 Copyright (c) 2000-2012 the FFmpeg
developers
built on Sep 20 2012 16:11:00 with gcc 4.5.3 (GCC)
configuration: --cc=/usr/local/gcc-4.5.3/bin/gcc --enable-gpl
libavutil 51. 73.101 / 51. 73.101
libavcodec 54. 56.100 / 54. 56.100
libavformat 54. 27.101 / 54. 27.101
libavdevice 54. 2.101 / 54. 2.101
libavfilter 3. 16.105 / 3. 16.105
libswscale 2. 1.101 / 2. 1.101
libswresample 0. 15.100 / 0. 15.100
libpostproc 52. 0.100 / 52. 0.100
[avi @ 0x14f0240] non-interleaved AVI
Input #0, avi, from
'016_avi_mpeg4_sp[720 at 24fps]_aac[2ch_128kbps_44.1khz].avi[MV]_origin.avi':
Metadata:
encoder : PotEncoder
Duration: 00:00:31.00, start: 0.000000, bitrate: 6907 kb/s
Stream #0:0: Video: mpeg4 (Simple Profile) (XVID / 0x44495658),
yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 24 tbr, 24 tbn, 24 tbc
Stream #0:1: Audio: aac ([255][0][0][0] / 0x00FF), 44100 Hz, stereo,
s16, 128 kb/s
Please use -q:a or -q:v, -qscale is ambiguous
Output #0, avi, to 'out.avi':
Metadata:
ISFT : Lavf54.27.101
Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 1280x720 [SAR
1:1 DAR 16:9], q=2-31, 200 kb/s, 24 tbn, 24 tbc
Stream #0:1: Audio: ac3 ([0] [0][0] / 0x2000), 44100 Hz, stereo, flt,
192 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (mpeg4 -> mpeg4)
Stream #0:1 -> #0:1 (aac -> ac3)
Press [q] to stop, [?] for help
[avi @ 0x150b000] st:0 PTS: 3 DTS: 3 < 6 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 3 DTS: 3 < 7 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 4 DTS: 4 < 8 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 5 DTS: 5 < 9 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 6 DTS: 6 < 10 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 5 DTS: 5 < 11 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 6 DTS: 6 < 12 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 7 DTS: 7 < 13 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 7 DTS: 7 < 14 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 7 DTS: 7 < 15 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 8 DTS: 8 < 16 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 8 DTS: 8 < 17 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 9 DTS: 9 < 18 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 9 DTS: 9 < 19 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 10 DTS: 10 < 20 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 9 DTS: 9 < 21 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 10 DTS: 10 < 22 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 11 DTS: 11 < 23 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 11 DTS: 11 < 24 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 11 DTS: 11 < 25 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 12 DTS: 12 < 26 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 12 DTS: 12 < 27 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 13 DTS: 13 < 28 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 13 DTS: 13 < 29 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 14 DTS: 14 < 30 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 14 DTS: 14 < 31 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 14 DTS: 14 < 32 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 15 DTS: 15 < 33 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 15 DTS: 15 < 34 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 15 DTS: 15 < 35 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 16 DTS: 16 < 36 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 16 DTS: 16 < 37 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 17 DTS: 17 < 38 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 17 DTS: 17 < 39 invalid, clipping
...
[avi @ 0x150b000] st:0 PTS: 341 DTS: 341 < 861 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 341 DTS: 341 < 862 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 341 DTS: 341 < 863 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 342 DTS: 342 < 864 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 342 DTS: 342 < 865 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 343 DTS: 343 < 866 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 343 DTS: 343 < 867 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 344 DTS: 344 < 868 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 343 DTS: 343 < 869 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 344 DTS: 344 < 870 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 344 DTS: 344 < 871 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 345 DTS: 345 < 872 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 345 DTS: 345 < 873 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 346 DTS: 346 < 874 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 346 DTS: 346 < 875 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 346 DTS: 346 < 876 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 347 DTS: 347 < 877 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 347 DTS: 347 < 878 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 347 DTS: 347 < 879 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 348 DTS: 348 < 880 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 349 DTS: 349 < 881 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 349 DTS: 349 < 882 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 349 DTS: 349 < 883 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 350 DTS: 350 < 884 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 350 DTS: 350 < 885 invalid, clipping
[avi @ 0x150b000] st:0 PTS: 350 DTS: 350 < 886 invalid, clipping
frame= 744 fps= 94 q=2.0 Lsize= 36906kB time=00:00:31.00
bitrate=9752.7kbits/s
video:36133kB audio:725kB subtitle:0 global headers:0kB muxing overhead
0.131191%
}}}
--
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/1755#comment:6>
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