[FFmpeg-trac] #6607(ffplay:new): ffplay has difficulty decoding 4.0 PCM
FFmpeg
trac at avcodec.org
Wed Aug 23 12:59:50 EEST 2017
#6607: ffplay has difficulty decoding 4.0 PCM
-----------------------------------+---------------------------------------
Reporter: kieranjol | Type: defect
Status: new | Priority: normal
Component: ffplay | Version: unspecified
Keywords: | Blocked By:
Blocking: | Reproduced by developer: 0
Analyzed by developer: 0 |
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Summary of the bug:
ffplay and VLC have issues playing 4.0 PCM audio, whether in WAV, MOV or
MKV containers. When making `sine` waves with `lavfi`, ffplay produces
silence for 4.0, though 2, 5, 6 channel audio is played back OK. VLC
produces throbbing, distoreted audio but that's outside of the scope of
this issue I guess.
How to reproduce:
Generate a sine wave with ffmpeg and then play it back with ffplay.
{{{
./ffmpeg -f lavfi -i "sine=frequency=1000:duration=5:sample_rate=48000"
-ac 4 -c:a pcm_s24le test.wav
ffmpeg version N-87034-geca2a49 Copyright (c) 2000-2017 the FFmpeg
developers
built with Apple LLVM version 7.3.0 (clang-703.0.31)
configuration:
libavutil 55. 74.100 / 55. 74.100
libavcodec 57.103.100 / 57.103.100
libavformat 57. 76.100 / 57. 76.100
libavdevice 57. 7.101 / 57. 7.101
libavfilter 6.100.100 / 6.100.100
libswscale 4. 7.102 / 4. 7.102
libswresample 2. 8.100 / 2. 8.100
Input #0, lavfi, from 'sine=frequency=1000:duration=5:sample_rate=48000':
Duration: N/A, start: 0.000000, bitrate: 768 kb/s
Stream #0:0: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
File 'test.wav' already exists. Overwrite ? [y/N] y
Stream mapping:
Stream #0:0 -> #0:0 (pcm_s16le (native) -> pcm_s24le (native))
Press [q] to stop, [?] for help
Output #0, wav, to 'test.wav':
Metadata:
ISFT : Lavf57.76.100
Stream #0:0: Audio: pcm_s24le ([1][0][0][0] / 0x0001), 48000 Hz, 4.0,
s32, 4608 kb/s
Metadata:
encoder : Lavc57.103.100 pcm_s24le
size= 2813kB time=00:00:05.00 bitrate=4608.2kbits/s speed= 432x
video:0kB audio:2812kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: 0.003542%
./ffplay test.wav
ffplay version N-87034-geca2a49 Copyright (c) 2003-2017 the FFmpeg
developers
built with Apple LLVM version 7.3.0 (clang-703.0.31)
configuration:
libavutil 55. 74.100 / 55. 74.100
libavcodec 57.103.100 / 57.103.100
libavformat 57. 76.100 / 57. 76.100
libavdevice 57. 7.101 / 57. 7.101
libavfilter 6.100.100 / 6.100.100
libswscale 4. 7.102 / 4. 7.102
libswresample 2. 8.100 / 2. 8.100
Input #0, wav, from 'test.wav':
Metadata:
encoder : Lavf57.76.100
Duration: 00:00:05.00, bitrate: 4608 kb/s
Stream #0:0: Audio: pcm_s24le ([1][0][0][0] / 0x0001), 48000 Hz, 4.0,
s32 (24 bit), 4608 kb/s
3.46 M-A: -0.000 fd= 0 aq= 577KB vq= 0KB sq= 0B f=0/0
}}}
Patches should be submitted to the ffmpeg-devel mailing list and not this
bug tracker.
--
Ticket URL: <https://trac.ffmpeg.org/ticket/6607>
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