Opened 2 years ago
Last modified 17 months ago
#9594 open enhancement
alac encoder does no support 20bits depth
Reported by: | Michael | Owned by: | |
---|---|---|---|
Priority: | wish | Component: | avcodec |
Version: | git-master | Keywords: | alac |
Cc: | Michael | Blocked By: | |
Blocking: | Reproduced by developer: | yes | |
Analyzed by developer: | no |
Description
Summary of the bug:
alac decoder support 20 bits bit depth, but encoder does not.
seems fixed bit depth in code of encoder.
libavcodec\alacenc.c
---
if (avctx->sample_fmt == AV_SAMPLE_FMT_S32P) {
if (avctx->bits_per_raw_sample != 24)
av_log(avctx, AV_LOG_WARNING, "encoding as 24 bits-per-sample\n");
avctx->bits_per_raw_sample = 24;
} else {
avctx->bits_per_raw_sample = 16;
s->extra_bits = 0;
}
---
How to reproduce:
C:\Data\ffmpeg.exe -i 009.caf -codec alac 009.m4a ffmpeg version n4.4.1-14-g5a7763bdfa-20220108 Copyright (c) 2000-2021 the FFmpeg developers built with gcc 11.2.0 (crosstool-NG 1.24.0.498_5075e1f) configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static --pkg-config=pkg-config --cross-prefix=x86_64-w64-mingw32- --arch=x86_64 --target-os=mingw32 --enable-nonfree --enable-gpl --enable-version3 --disable-debug --enable-shared --disable-static --disable-w32threads --enable-pthreads --enable-iconv --enable-libxml2 --enable-zlib --enable-libfreetype --enable-libfribidi --enable-gmp --enable-lzma --enable-fontconfig --enable-libvorbis --enable-opencl --disable-libpulse --enable-libvmaf --disable-libxcb --disable-xlib --enable-amf --enable-libaom --enable-avisynth --enable-libdav1d --enable-libdavs2 --enable-libfdk-aac --enable-ffnvcodec --enable-cuda-llvm --disable-frei0r --enable-libgme --enable-libass --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librist --enable-libtheora --enable-libvpx --enable-libwebp --enable-lv2 --enable-libmfx --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopenmpt --enable-librav1e --enable-librubberband --enable-schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libsvtav1 --enable-libtwolame --enable-libuavs3d --disable-libdrm --disable-vaapi --enable-libvidstab --disable-vulkan --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libzimg --enable-libzvbi --extra-cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-ldflags=-pthread --extra-ldexeflags= --extra-libs=-lgomp --extra-version=20220108 libavutil 56. 70.100 / 56. 70.100 libavcodec 58.134.100 / 58.134.100 libavformat 58. 76.100 / 58. 76.100 libavdevice 58. 13.100 / 58. 13.100 libavfilter 7.110.100 / 7.110.100 libswscale 5. 9.100 / 5. 9.100 libswresample 3. 9.100 / 3. 9.100 libpostproc 55. 9.100 / 55. 9.100 Input #0, caf, from '009.caf': Duration: 00:01:35.02, start: 0.000000, bitrate: 793 kb/s Stream #0:0: Audio: alac (alac / 0x63616C61), 44100 Hz, stereo, s32p (20 bit), 705 kb/s Stream mapping: Stream #0:0 -> #0:0 (alac (native) -> alac (native)) Press [q] to stop, [?] for help [alac @ 000002e1e6d4f000] encoding as 24 bits-per-sample Output #0, ipod, to '009.m4a': Metadata: encoder : Lavf58.76.100 Stream #0:0: Audio: alac (alac / 0x63616C61), 44100 Hz, stereo, s32p (24 bit), 128 kb/s Metadata: encoder : Lavc58.134.100 alac size= 13663kB time=00:01:34.92 bitrate=1179.2kbits/s speed= 162x video:0kB audio:13658kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.035743%
Attachments (1)
Change History (5)
by , 2 years ago
comment:1 by , 2 years ago
Cc: | added |
---|---|
Version: | unspecified → 4.4.1 |
follow-up: 3 comment:2 by , 2 years ago
LOL, actually 24 bit LAC in HW is not supported without this patch of mine (author is Davis). https://patchwork.ffmpeg.org/project/ffmpeg/patch/20210531150302.359628-1-val.zapod.vz@gmail.com/
comment:3 by , 2 years ago
Replying to Balling:
thank you Balling, but how to solve 20 bits problem?
LOL, actually 24 bit LAC in HW is not supported without this patch of mine (author is Davis). https://patchwork.ffmpeg.org/project/ffmpeg/patch/20210531150302.359628-1-val.zapod.vz@gmail.com/
comment:4 by , 17 months ago
Keywords: | alac added |
---|---|
Priority: | normal → wish |
Reproduced by developer: | set |
Status: | new → open |
Type: | defect → enhancement |
Version: | 4.4.3 → git-master |
009.caf