#11656: -bitexact does not remove metadata encoder tag in OGG Vorbis files
-------------------------------------+-------------------------------------
Reporter: Iwan | Type: defect
Gabovitch |
Status: new | Priority: normal
Component: ffmpeg | Version: git-
| master
Keywords: | Blocked By:
Blocking: | Reproduced by developer: 0
Analyzed by developer: 0 |
-------------------------------------+-------------------------------------
Summary of the bug:
`-bitexact` removes the metadata encoder tag for wav, flac and mp3 files,
but not for ogg files.
Let's generate a wav:
{{{
$ ffmpeg -f lavfi -i "sine=frequency=1000:duration=0.1:sample_rate=44100"
-af "volume=0.2" input.wav
ffmpeg version 2025-07-01-git-11d1b71c31-full_build-www.gyan.dev Copyright
(c) 2000-2025 the FFmpeg developers
built with gcc 15.1.0 (Rev4, Built by MSYS2 project)
configuration: --enable-gpl --enable-version3 --enable-static --disable-
w32threads --disable-autodetect --enable-fontconfig --enable-iconv
--enable-gnutls --enable-lcms2 --enable-libxml2 --enable-gmp --enable-
bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist
--enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth
--enable-libbluray --enable-libcaca --enable-libdvdnav --enable-libdvdread
--enable-sdl2 --enable-libaribb24 --enable-libaribcaption --enable-
libdav1d --enable-libdavs2 --enable-libopenjpeg --enable-libquirc
--enable-libuavs3d --enable-libxevd --enable-libzvbi --enable-liboapv
--enable-libqrencode --enable-librav1e --enable-libsvtav1 --enable-
libvvenc --enable-libwebp --enable-libx264 --enable-libx265 --enable-
libxavs2 --enable-libxeve --enable-libxvid --enable-libaom --enable-libjxl
--enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r
--enable-libfreetype --enable-libfribidi --enable-libharfbuzz --enable-
liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-
amf --enable-cuda-llvm --enable-cuvid --enable-dxva2 --enable-d3d11va
--enable-d3d12va --enable-ffnvcodec --enable-libvpl --enable-nvdec
--enable-nvenc --enable-vaapi --enable-libshaderc --enable-vulkan
--enable-libplacebo --enable-opencl --enable-libcdio --enable-openal
--enable-libgme --enable-libmodplug --enable-libopenmpt --enable-
libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora
--enable-libtwolame --enable-libvo-amrwbenc --enable-libcodec2 --enable-
libilbc --enable-libgsm --enable-liblc3 --enable-libopencore-amrnb
--enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa
--enable-libbs2b --enable-libflite --enable-libmysofa --enable-
librubberband --enable-libsoxr --enable-chromaprint
libavutil 60. 4.101 / 60. 4.101
libavcodec 62. 4.103 / 62. 4.103
libavformat 62. 1.101 / 62. 1.101
libavdevice 62. 0.100 / 62. 0.100
libavfilter 11. 0.100 / 11. 0.100
libswscale 9. 0.100 / 9. 0.100
libswresample 6. 0.100 / 6. 0.100
[out @ 00000187e0830640] The "sample_fmts" option is deprecated: set the
supported sample formats
[out @ 00000187e0830640] The "all_channel_counts" option is deprecated:
accept all channel counts
Input #0, lavfi, from
'sine=frequency=1000:duration=0.1:sample_rate=44100':
Duration: N/A, start: 0.000000, bitrate: 705 kb/s
Stream #0:0: Audio: pcm_s16le, 44100 Hz, mono, s16, 705 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (pcm_s16le (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
Output #0, wav, to 'input.wav':
Metadata:
ISFT : Lavf62.1.101
Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, mono,
s16, 705 kb/s
Metadata:
encoder : Lavc62.4.103 pcm_s16le
[out#0/wav @ 00000187e082f500] video:0KiB audio:9KiB subtitle:0KiB other
streams:0KiB global headers:0KiB muxing overhead: 0.884354%
size= 9KiB time=00:00:00.10 bitrate= 711.8kbits/s speed=58.7x
elapsed=0:00:00.00
}}}
Let's confirm the metadata:
{{{
$ ffprobe.exe -hide_banner input.wav
Input #0, wav, from 'input.wav':
Metadata:
encoder : Lavf62.1.101
Duration: 00:00:00.10, bitrate: 711 kb/s
Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, 1
channels, s16, 705 kb/s
}}}
Let's convert to flac with `-bitexact`:
{{{
$ ffmpeg -hide_banner -i input.wav -bitexact output.flac
[aist#0:0/pcm_s16le @ 00000205f2020900] Guessed Channel Layout: mono
Input #0, wav, from 'input.wav':
Metadata:
encoder : Lavf62.1.101
Duration: 00:00:00.10, bitrate: 711 kb/s
Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, mono,
s16, 705 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (pcm_s16le (native) -> flac (native))
Press [q] to stop, [?] for help
Output #0, flac, to 'output.flac':
Stream #0:0: Audio: flac, 44100 Hz, mono, s16, 128 kb/s
Metadata:
encoder : Lavc flac
[out#0/flac @ 00000205f2021bc0] video:0KiB audio:1KiB subtitle:0KiB other
streams:0KiB global headers:0KiB muxing overhead: 707.455013%
size= 9KiB time=00:00:00.10 bitrate= 753.8kbits/s speed=42.3x
elapsed=0:00:00.00
}}}
Even though the output shows `encoder` `: Lavc flac`, it does not get
written:
{{{
$ ffprobe.exe -hide_banner output.flac
Input #0, flac, from 'output.flac':
Duration: 00:00:00.10, bitrate: 753 kb/s
Stream #0:0: Audio: flac, 44100 Hz, mono, s16
}}}
Let's convert to ogg with `-bitexact`:
{{{
$ ffmpeg -hide_banner -i input.wav -bitexact output.ogg
[aist#0:0/pcm_s16le @ 00000256f3f20900] Guessed Channel Layout: mono
Input #0, wav, from 'input.wav':
Metadata:
encoder : Lavf62.1.101
Duration: 00:00:00.10, bitrate: 711 kb/s
Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, mono,
s16, 705 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (pcm_s16le (native) -> vorbis (libvorbis))
Press [q] to stop, [?] for help
Output #0, ogg, to 'output.ogg':
Stream #0:0: Audio: vorbis, 44100 Hz, mono, fltp
Metadata:
encoder : Lavc libvorbis
[out#0/ogg @ 00000256f3f21bc0] video:0KiB audio:0KiB subtitle:0KiB other
streams:0KiB global headers:3KiB muxing overhead: 743.708609%
size= 4KiB time=00:00:00.10 bitrate= 305.8kbits/s speed=9.99x
elapsed=0:00:00.01
}}}
This time, the metadata is in the file:
{{{
$ ffprobe.exe -hide_banner output.ogg
Input #0, ogg, from 'output.ogg':
Duration: 00:00:00.10, start: 0.000000, bitrate: 305 kb/s
Stream #0:0: Audio: vorbis, 44100 Hz, mono, fltp, 80 kb/s
Metadata:
encoder : Lavc libvorbis
}}}
--
Ticket URL: <https://trac.ffmpeg.org/ticket/11656>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker
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