[FFmpeg-trac] #5310(avcodec:new): mpegts demuxer ignores the amount of samples it should drop from the last Opus frame
FFmpeg
trac at avcodec.org
Mon Mar 7 20:21:05 CET 2016
#5310: mpegts demuxer ignores the amount of samples it should drop from the last
Opus frame
-------------------------------------+-------------------------------------
Reporter: jamrial | Type: defect
Status: new | Priority: normal
Component: avcodec | Version: git-
Keywords: opus mpegts | master
Blocking: | Blocked By:
Analyzed by developer: 0 | Reproduced by developer: 0
-------------------------------------+-------------------------------------
{{{
$ ./ffmpeg -v 0 -f lavfi -i
"aevalsrc=cos(2*PI*t)*sin(2*PI*(440+4*t)*t)::d=20" -ac 2 -c:a libopus -y
test.mka && ./ffmpeg -i test.mka -f md5 -
ffmpeg version N-78958-g8c24523 Copyright (c) 2000-2016 the FFmpeg
developers
built with gcc 5.3.0 (Rev2, Built by MSYS2 project)
configuration: --enable-gpl --enable-nonfree --enable-libfdk-aac
--enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx
--enable-libwebp --enable-libx264 --enable-libx265 --enable-opengl
--target-os=mingw32 --arch=x86_64 --cpu=haswell --extra-
cflags='-D_WIN32_WINNT=0x0600' --samples=../samples --prefix=/mingw64
libavutil 55. 19.100 / 55. 19.100
libavcodec 57. 28.100 / 57. 28.100
libavformat 57. 28.100 / 57. 28.100
libavdevice 57. 0.101 / 57. 0.101
libavfilter 6. 39.102 / 6. 39.102
libswscale 4. 0.100 / 4. 0.100
libswresample 2. 0.101 / 2. 0.101
libpostproc 54. 0.100 / 54. 0.100
Input #0, matroska,webm, from 'test.mka':
Metadata:
ENCODER : Lavf57.28.100
Duration: 00:00:20.02, start: 0.007000, bitrate: 160 kb/s
Stream #0:0: Audio: opus, 48000 Hz, stereo, fltp (default)
Metadata:
ENCODER : Lavc57.28.100 libopus
DURATION : 00:00:20.023000000
Output #0, md5, to 'pipe:':
Metadata:
encoder : Lavf57.28.100
Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
(default)
Metadata:
DURATION : 00:00:20.023000000
encoder : Lavc57.28.100 pcm_s16le
Stream mapping:
Stream #0:0 -> #0:0 (opus (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
MD5=8a31a3522806e330cb9200b29848b480
size= 0kB time=00:00:20.02 bitrate= 0.0kbits/s speed= 223x
video:0kB audio:3754kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: unknown
$ ./ffmpeg -v 0 -f lavfi -i
"aevalsrc=cos(2*PI*t)*sin(2*PI*(440+4*t)*t)::d=20" -ac 2 -c:a libopus -y
test.opus && ./ffmpeg -i test.opus -f md5 -
ffmpeg version N-78958-g8c24523 Copyright (c) 2000-2016 the FFmpeg
developers
built with gcc 5.3.0 (Rev2, Built by MSYS2 project)
configuration: --enable-gpl --enable-nonfree --enable-libfdk-aac
--enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx
--enable-libwebp --enable-libx264 --enable-libx265 --enable-opengl
--target-os=mingw32 --arch=x86_64 --cpu=haswell --extra-
cflags='-D_WIN32_WINNT=0x0600' --samples=../samples --prefix=/mingw64
libavutil 55. 19.100 / 55. 19.100
libavcodec 57. 28.100 / 57. 28.100
libavformat 57. 28.100 / 57. 28.100
libavdevice 57. 0.101 / 57. 0.101
libavfilter 6. 39.102 / 6. 39.102
libswscale 4. 0.100 / 4. 0.100
libswresample 2. 0.101 / 2. 0.101
libpostproc 54. 0.100 / 54. 0.100
Input #0, ogg, from 'test.opus':
Duration: 00:00:20.02, start: 0.000000, bitrate: 158 kb/s
Stream #0:0: Audio: opus, 48000 Hz, stereo, fltp
Metadata:
ENCODER : Lavc57.28.100 libopus
Output #0, md5, to 'pipe:':
Metadata:
encoder : Lavf57.28.100
Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Metadata:
encoder : Lavc57.28.100 pcm_s16le
Stream mapping:
Stream #0:0 -> #0:0 (opus (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
MD5=8a31a3522806e330cb9200b29848b480
size= 0kB time=00:00:20.01 bitrate= 0.0kbits/s speed= 232x
video:0kB audio:3754kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: unknown
$ ./ffmpeg -v 0 -f lavfi -i
"aevalsrc=cos(2*PI*t)*sin(2*PI*(440+4*t)*t)::d=20" -ac 2 -c:a libopus -y
test.ts && ./ffmpeg -i test.ts -f md5 -
ffmpeg version N-78958-g8c24523 Copyright (c) 2000-2016 the FFmpeg
developers
built with gcc 5.3.0 (Rev2, Built by MSYS2 project)
configuration: --enable-gpl --enable-nonfree --enable-libfdk-aac
--enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx
--enable-libwebp --enable-libx264 --enable-libx265 --enable-opengl
--target-os=mingw32 --arch=x86_64 --cpu=haswell --extra-
cflags='-D_WIN32_WINNT=0x0600' --samples=../samples --prefix=/mingw64
libavutil 55. 19.100 / 55. 19.100
libavcodec 57. 28.100 / 57. 28.100
libavformat 57. 28.100 / 57. 28.100
libavdevice 57. 0.101 / 57. 0.101
libavfilter 6. 39.102 / 6. 39.102
libswscale 4. 0.100 / 4. 0.100
libswresample 2. 0.101 / 2. 0.101
libpostproc 54. 0.100 / 54. 0.100
Input #0, mpegts, from 'test.ts':
Duration: 00:00:20.00, start: 1.400000, bitrate: 182 kb/s
Program 1
Metadata:
service_name : Service01
service_provider: FFmpeg
Stream #0:0[0x100]: Audio: opus (Opus / 0x7375704F), 48000 Hz, stereo,
fltp
Output #0, md5, to 'pipe:':
Metadata:
encoder : Lavf57.28.100
Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Metadata:
encoder : Lavc57.28.100 pcm_s16le
Stream mapping:
Stream #0:0 -> #0:0 (opus (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
MD5=370faa46e5371aa3f65a54bee8ef402a
size= 0kB time=00:00:20.04 bitrate= 0.0kbits/s speed= 228x
video:0kB audio:3758kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: unknown
}}}
If you add -loglevel debug when decoding the Matroska and OggOpus files
you get the following:
{{{
[opus @ 0000016b4bb2a6c0] skip 0 / discard 859 samples due to side data
[opus @ 0000016b4bb2a6c0] discard 859/960 samples
[output stream 0:0 @ 0000016b4bb2ec60] EOF on sink link output stream
0:0:default.
No more output streams to write to, finishing.
MD5=8a31a3522806e330cb9200b29848b480
size= 0kB time=00:00:20.01 bitrate= 0.0kbits/s speed= 233x
video:0kB audio:3754kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: unknown
Input file #0 (test.opus):
Input stream #0:0 (audio): 1002 packets read (394264 bytes); 1002 frames
decoded (961061 samples);
Total: 1002 packets (394264 bytes) demuxed
Output file #0 (pipe:):
Output stream #0:0 (audio): 1002 frames encoded (961061 samples); 1002
packets muxed (3844244 bytes);
Total: 1002 packets (3844244 bytes) muxed
}}}
Whereas the mpegts file reports
{{{
[output stream 0:0 @ 0000028b48dc2800] EOF on sink link output stream
0:0:default.
No more output streams to write to, finishing.
MD5=370faa46e5371aa3f65a54bee8ef402a
size= 0kB time=00:00:20.04 bitrate= 0.0kbits/s speed= 232x
video:0kB audio:3758kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: unknown
Input file #0 (test.ts):
Input stream #0:0 (audio): 1002 packets read (397055 bytes); 1002 frames
decoded (961920 samples);
Total: 1002 packets (397055 bytes) demuxed
Output file #0 (pipe:):
Output stream #0:0 (audio): 1002 frames encoded (961920 samples); 1002
packets muxed (3847680 bytes);
Total: 1002 packets (3847680 bytes) muxed
1002 frames successfully decoded, 0 decoding errors
}}}
Notice the lack of discarded samples debug messages, and the amount of
samples the latter decoded.
Our mpegts muxer adds this information (Opus specific code in
mpegts_write_packet_internal() from mpegtsenc.o), but the demuxer is
unaware of it. It's all handled and ignored by the Opus parser in
libavcodec instead.
--
Ticket URL: <https://trac.ffmpeg.org/ticket/5310>
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