Opened 3 months ago

Last modified 3 months ago

#6367 open defect

ogg vorbis decode results in too many sample frames

Reported by: markbuer Owned by:
Priority: normal Component: undetermined
Version: git-master Keywords: ogg vorbis
Cc: Blocked By:
Blocking: Reproduced by developer: yes
Analyzed by developer: no

Description

Decoding ogg vorbis via ffmpeg results in too many sample frames, as compared with the original (pre encoded) raw file or the oggdec tool.

Chromium issue https://bugs.chromium.org/p/chromium/issues/detail?id=456252


Simple reproduction steps:

# Create 125 sample frames of raw (44.1kHz stereo pcm_s16le) silence
dd if=/dev/zero of=./silence.raw count=1 bs=500

# Encode raw to ogg vorbis
oggenc --raw silence.raw --output=silence.ogg

# Decode ogg vorbis to raw using oggdec
oggdec --raw --output silence.oggdec.raw silence.ogg

# Decode ogg vorbis to raw using ffmpeg libvorbis decoder
ffmpeg -codec:a libvorbis -i silence.ogg -f s16le -codec:a pcm_s16le silence.libvorbis.ffmpeg.raw

# Decode ogg vorbis to raw using ffmpeg native decoder
ffmpeg -i silence.ogg -f s16le -codec:a pcm_s16le silence.native.ffmpeg.raw

# Examine the results of decoding
# We expect all raw files to have identical size,
# but instead we see that the ffmpeg decoded files are too big
ls -l *.raw

# Repeat with different sized initial raw file to see that the
# problem occurs for any number of initial sample frames (small or large)

Output from ls *.raw:

-rw-r--r--  1 mark  staff      2304  3 May 07:15 silence.libvorbis.ffmpeg.raw
-rw-r--r--  1 mark  staff      2304  3 May 07:16 silence.native.ffmpeg.raw
-rw-r--r--  1 mark  staff       500  3 May 07:14 silence.oggdec.raw
-rw-r--r--  1 mark  staff       500  3 May 07:12 silence.raw

-report output for libvorbis decode invocation:

ffmpeg started on 2017-05-03 at 08:30:15
Report written to "ffmpeg-20170503-083015.log"
Command line:
ffmpeg -report -codec:a libvorbis -i silence.ogg -f s16le -codec:a pcm_s16le silence.libvorbis.ffmpeg.raw
ffmpeg version git-2017-05-02-20da413 Copyright (c) 2000-2017 the FFmpeg developers
  built with Apple LLVM version 8.1.0 (clang-802.0.42)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/HEAD-20da413 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-opencl --disable-lzma --enable-nonfree --enable-vda
  libavutil      55. 61.100 / 55. 61.100
  libavcodec     57. 93.100 / 57. 93.100
  libavformat    57. 72.101 / 57. 72.101
  libavdevice    57.  7.100 / 57.  7.100
  libavfilter     6. 88.100 /  6. 88.100
  libavresample   3.  6.  0 /  3.  6.  0
  libswscale      4.  7.101 /  4.  7.101
  libswresample   2.  8.100 /  2.  8.100
  libpostproc    54.  6.100 / 54.  6.100
Splitting the commandline.
Reading option '-report' ... matched as option 'report' (generate a report) with argument '1'.
Reading option '-codec:a' ... matched as option 'codec' (codec name) with argument 'libvorbis'.
Reading option '-i' ... matched as input url with argument 'silence.ogg'.
Reading option '-f' ... matched as option 'f' (force format) with argument 's16le'.
Reading option '-codec:a' ... matched as option 'codec' (codec name) with argument 'pcm_s16le'.
Reading option 'silence.libvorbis.ffmpeg.raw' ... matched as output url.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option report (generate a report) with argument 1.
Successfully parsed a group of options.
Parsing a group of options: input url silence.ogg.
Applying option codec:a (codec name) with argument libvorbis.
Successfully parsed a group of options.
Opening an input file: silence.ogg.
[file @ 0x7fe038e00520] Setting default whitelist 'file,crypto'
[ogg @ 0x7fe039801000] Format ogg probed with size=2048 and score=100
[ogg @ 0x7fe039801000] Before avformat_find_stream_info() pos: 4025 bytes read:4025 seeks:0 nb_streams:1
[ogg @ 0x7fe039801000] All info found
[ogg @ 0x7fe039801000] After avformat_find_stream_info() pos: 4025 bytes read:4025 seeks:0 frames:1
Guessed Channel Layout for Input Stream #0.0 : stereo
Input #0, ogg, from 'silence.ogg':
  Duration: 00:00:00.00, start: 0.000000, bitrate: 11362 kb/s
    Stream #0:0, 1, 1/44100: Audio: vorbis, 44100 Hz, stereo, s16, 112 kb/s
Successfully opened the file.
Parsing a group of options: output url silence.libvorbis.ffmpeg.raw.
Applying option f (force format) with argument s16le.
Applying option codec:a (codec name) with argument pcm_s16le.
Successfully parsed a group of options.
Opening an output file: silence.libvorbis.ffmpeg.raw.
[file @ 0x7fe038e020e0] Setting default whitelist 'file,crypto'
Successfully opened the file.
Stream mapping:
  Stream #0:0 -> #0:0 (vorbis (libvorbis) -> pcm_s16le (native))
Press [q] to stop, [?] for help
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
detected 4 logical cores
[graph_0_in_0_0 @ 0x7fe038f002a0] Setting 'time_base' to value '1/44100'
[graph_0_in_0_0 @ 0x7fe038f002a0] Setting 'sample_rate' to value '44100'
[graph_0_in_0_0 @ 0x7fe038f002a0] Setting 'sample_fmt' to value 's16'
[graph_0_in_0_0 @ 0x7fe038f002a0] Setting 'channel_layout' to value '0x3'
[graph_0_in_0_0 @ 0x7fe038f002a0] tb:1/44100 samplefmt:s16 samplerate:44100 chlayout:0x3
[format_out_0_0 @ 0x7fe038f00840] Setting 'sample_fmts' to value 's16'
[AVFilterGraph @ 0x7fe038e0bf20] query_formats: 4 queried, 9 merged, 0 already done, 0 delayed
Output #0, s16le, to 'silence.libvorbis.ffmpeg.raw':
  Metadata:
    encoder         : Lavf57.72.101
    Stream #0:0, 0, 1/44100: Audio: pcm_s16le, 44100 Hz, stereo, s16, 1411 kb/s
    Metadata:
      encoder         : Lavc57.93.100 pcm_s16le
No more output streams to write to, finishing.
size=       2kB time=00:00:00.01 bitrate=1154.6kbits/s speed=21.3x    
video:0kB audio:2kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000000%
Input file #0 (silence.ogg):
  Input stream #0:0 (audio): 2 packets read (2 bytes); 1 frames decoded (576 samples); 
  Total: 2 packets (2 bytes) demuxed
Output file #0 (silence.libvorbis.ffmpeg.raw):
  Output stream #0:0 (audio): 1 frames encoded (576 samples); 1 packets muxed (2304 bytes); 
  Total: 1 packets (2304 bytes) muxed
1 frames successfully decoded, 0 decoding errors
[AVIOContext @ 0x7fe038e02160] Statistics: 0 seeks, 1 writeouts
[AVIOContext @ 0x7fe038e00660] Statistics: 4025 bytes read, 0 seeks

-report output for native decode invocation:

ffmpeg started on 2017-05-03 at 08:22:13
Report written to "ffmpeg-20170503-082213.log"
Command line:
ffmpeg -report -i silence.ogg -f s16le -codec:a pcm_s16le silence.native.ffmpeg.raw
ffmpeg version git-2017-05-02-20da413 Copyright (c) 2000-2017 the FFmpeg developers
  built with Apple LLVM version 8.1.0 (clang-802.0.42)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/HEAD-20da413 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-opencl --disable-lzma --enable-nonfree --enable-vda
  libavutil      55. 61.100 / 55. 61.100
  libavcodec     57. 93.100 / 57. 93.100
  libavformat    57. 72.101 / 57. 72.101
  libavdevice    57.  7.100 / 57.  7.100
  libavfilter     6. 88.100 /  6. 88.100
  libavresample   3.  6.  0 /  3.  6.  0
  libswscale      4.  7.101 /  4.  7.101
  libswresample   2.  8.100 /  2.  8.100
  libpostproc    54.  6.100 / 54.  6.100
Splitting the commandline.
Reading option '-report' ... matched as option 'report' (generate a report) with argument '1'.
Reading option '-i' ... matched as input url with argument 'silence.ogg'.
Reading option '-f' ... matched as option 'f' (force format) with argument 's16le'.
Reading option '-codec:a' ... matched as option 'codec' (codec name) with argument 'pcm_s16le'.
Reading option 'silence.native.ffmpeg.raw' ... matched as output url.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option report (generate a report) with argument 1.
Successfully parsed a group of options.
Parsing a group of options: input url silence.ogg.
Successfully parsed a group of options.
Opening an input file: silence.ogg.
[file @ 0x7fadd4d0f580] Setting default whitelist 'file,crypto'
[ogg @ 0x7fadd5010200] Format ogg probed with size=2048 and score=100
[ogg @ 0x7fadd5010200] Before avformat_find_stream_info() pos: 4025 bytes read:4025 seeks:0 nb_streams:1
[ogg @ 0x7fadd5010200] All info found
[ogg @ 0x7fadd5010200] After avformat_find_stream_info() pos: 4025 bytes read:4025 seeks:0 frames:1
Input #0, ogg, from 'silence.ogg':
  Duration: 00:00:00.00, start: 0.000000, bitrate: 11362 kb/s
    Stream #0:0, 1, 1/44100: Audio: vorbis, 44100 Hz, stereo, fltp, 112 kb/s
Successfully opened the file.
Parsing a group of options: output url silence.native.ffmpeg.raw.
Applying option f (force format) with argument s16le.
Applying option codec:a (codec name) with argument pcm_s16le.
Successfully parsed a group of options.
Opening an output file: silence.native.ffmpeg.raw.
[file @ 0x7fadd4d10540] Setting default whitelist 'file,crypto'
Successfully opened the file.
Stream mapping:
  Stream #0:0 -> #0:0 (vorbis (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
detected 4 logical cores
[graph_0_in_0_0 @ 0x7fadd4d13ee0] Setting 'time_base' to value '1/44100'
[graph_0_in_0_0 @ 0x7fadd4d13ee0] Setting 'sample_rate' to value '44100'
[graph_0_in_0_0 @ 0x7fadd4d13ee0] Setting 'sample_fmt' to value 'fltp'
[graph_0_in_0_0 @ 0x7fadd4d13ee0] Setting 'channel_layout' to value '0x3'
[graph_0_in_0_0 @ 0x7fadd4d13ee0] tb:1/44100 samplefmt:fltp samplerate:44100 chlayout:0x3
[format_out_0_0 @ 0x7fadd4d14480] Setting 'sample_fmts' to value 's16'
[format_out_0_0 @ 0x7fadd4d14480] auto-inserting filter 'auto_resampler_0' between the filter 'Parsed_anull_0' and the filter 'format_out_0_0'
[AVFilterGraph @ 0x7fadd4d13980] query_formats: 4 queried, 6 merged, 3 already done, 0 delayed
[auto_resampler_0 @ 0x7fadd4d14c80] [SWR @ 0x7fadd506f400] Using fltp internally between filters
[auto_resampler_0 @ 0x7fadd4d14c80] ch:2 chl:stereo fmt:fltp r:44100Hz -> ch:2 chl:stereo fmt:s16 r:44100Hz
Output #0, s16le, to 'silence.native.ffmpeg.raw':
  Metadata:
    encoder         : Lavf57.72.101
    Stream #0:0, 0, 1/44100: Audio: pcm_s16le, 44100 Hz, stereo, s16, 1411 kb/s
    Metadata:
      encoder         : Lavc57.93.100 pcm_s16le
No more output streams to write to, finishing.
size=       2kB time=00:00:00.01 bitrate=1154.6kbits/s speed=19.1x    
video:0kB audio:2kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000000%
Input file #0 (silence.ogg):
  Input stream #0:0 (audio): 2 packets read (2 bytes); 1 frames decoded (576 samples); 
  Total: 2 packets (2 bytes) demuxed
Output file #0 (silence.native.ffmpeg.raw):
  Output stream #0:0 (audio): 1 frames encoded (576 samples); 1 packets muxed (2304 bytes); 
  Total: 1 packets (2304 bytes) muxed
1 frames successfully decoded, 0 decoding errors
[AVIOContext @ 0x7fadd4d10600] Statistics: 0 seeks, 1 writeouts
[AVIOContext @ 0x7fadd4d0f6c0] Statistics: 4025 bytes read, 0 seeks

Patches should be submitted to the ffmpeg-devel mailing list and not this bug tracker.

Change History (1)

comment:1 Changed 3 months ago by cehoyos

  • Keywords ogg vorbis added
  • Reproduced by developer set
  • Status changed from new to open
  • Version changed from unspecified to git-master

Not a regression afaict.

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