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• dcadec : simplify decoding of VQ high frequencies

  14 février 2014, par Christophe Gisquet

  dcadec : simplify decoding of VQ high frequencies
  The vector dequantization has a test in a loop preventing effective SIMD
  
  implementation. By moving it out of the loop, this loop can be DSPized.
  Therefore, modify the current DSP implementation. In particular, the
  
  DSP implementation no longer has to handle null loop sizes.
  The decode_hf implementations have following timings :
  For x86 Arrandale :
  
          C  SSE SSE2 SSE4
  
  win32 : 260 162  119  104
  
  win64 : 242 N/A   89   72
  The arm NEON optimizations follow in a later patch as external asm. The
  
  now unused check for the y modifier in arm inline asm is removed from
  
  configure.
  

  • [DBH] configure
  • [DBH] libavcodec/arm/dca.h
  • [DBH] libavcodec/dcadec.c
  • [DBH] libavcodec/dcadsp.c
  • [DBH] libavcodec/dcadsp.h
  • [DBH] libavcodec/x86/dcadsp.asm
  • [DBH] libavcodec/x86/dcadsp_init.c

• compiling ffmpeg for Mac OSX High Sierra 10.13

  29 juillet 2021, par Martin

  Hello I made an electron app that uses ffmpeg to combine audio and renders video, it works fine on windows, linux, and modern mac osx computers, but a user has reported to me that on an older version of mac osx such as High Sierra 10.13, the way that I have setup ffmpeg does not work.

  


  I have a virtual machine with High Sierra v10.13 where I install RenderTune-mac.dmg from my RenderTune releases page, then I download 2 audio files and the image from this link. I open RenderTune, and try render a video. My command to combine the audio files into a single mp3 works fine, but when I try to combine that mp3 with the image file, the ffmpeg build I have packaged with my electron app fails with this error :

  


  Command was killed with SIGABRT (Aborted): /Applications/RenderTune.app/Contents/Resources/ffmpeg -loop 1 -framerate 2 -i /Users/martin/Downloads/R-3777978-1344032418-8379.jpeg.jpg -i /Users/martin/Downloads/output-871140.mp3 -y -acodec copy -b:a 320k -vcodec libx264 -b:v 8000k -maxrate 8000k -minrate 8000k -bufsize 3M -filter:v scale=w=1920:h=1954 -preset medium -tune stillimage -crf 18 -pix_fmt yuv420p -shortest /Users/martin/Downloads/concatVideo-871140.mp4
ffmpeg version git-2021-03-24-13335df Copyright (c) 2000-2021 the FFmpeg developers
  built with Apple LLVM version 10.0.1 (clang-1001.0.46.4)
  configuration: --pkgconfigdir=/Users/martinbarker/Documents/projects/rendertune-0.5.0/workspace/lib/pkgconfig --prefix=/Users/martinbarker/Documents/projects/rendertune-0.5.0/workspace --pkg-config-flags=--static --extra-cflags='-I/Users/martinbarker/Documents/projects/rendertune-0.5.0/workspace/include -mmacosx-version-min=10.10' --extra-ldflags='-L/Users/martinbarker/Documents/projects/rendertune-0.5.0/workspace/lib -mmacosx-version-min=10.10' --extra-libs='-lpthread -lm' --enable-static --disable-securetransport --disable-debug --disable-shared --disable-ffplay --disable-lzma --disable-doc --enable-version3 --enable-pthreads --enable-runtime-cpudetect --enable-avfilter --enable-filters --disable-libxcb --enable-gpl --enable-nonfree --disable-libass --enable-libfdk-aac --enable-libmp3lame --enable-libx264
  libavutil      56. 66.100 / 56. 66.100
  libavcodec     58.128.100 / 58.128.100
  libavformat    58. 69.100 / 58. 69.100
  libavdevice    58. 12.100 / 58. 12.100
  libavfilter     7.107.100 /  7.107.100
  libswscale      5.  8.100 /  5.  8.100
  libswresample   3.  8.100 /  3.  8.100
  libpostproc    55.  8.100 / 55.  8.100
Input #0, image2, from '/Users/martin/Downloads/R-3777978-1344032418-8379.jpeg.jpg':
  Duration: 00:00:00.50, start: 0.000000, bitrate: 1758 kb/s
  Stream #0:0: Video: mjpeg (Progressive), yuvj444p(pc, bt470bg/unknown/unknown), 590x600 [SAR 1:1 DAR 59:60], 2 fps, 2 tbr, 2 tbn, 2 tbc
Input #1, mp3, from '/Users/martin/Downloads/output-871140.mp3':
  Metadata:
    title           : My Little Grass Shack
    album           : Our Hawaii - A Collection Of Personal Favorites
    artist          : Society Of Seven
    track           : 11
    encoder         : Lavf58.69.100
  Duration: 00:06:25.59, start: 0.025057, bitrate: 320 kb/s
  Stream #1:0: Audio: mp3, 44100 Hz, stereo, fltp, 320 kb/s
    Metadata:
      encoder         : Lavc58.12
Stream mapping:
  Stream #0:0 -> #0:0 (mjpeg (native) -> h264 (libx264))
  Stream #1:0 -> #0:1 (copy)
Press [q] to stop, [?] for help
[swscaler @ 0x7fbad9167600] deprecated pixel format used, make sure you did set range correctly
[libx264 @ 0x7fbad9040400] using SAR=2681/2679
dyld: lazy symbol binding failed: Symbol not found: ____chkstk_darwin
  Referenced from: /Applications/RenderTune.app/Contents/Resources/ffmpeg
  Expected in: /usr/lib/libSystem.B.dylib

dyld: Symbol not found: ____chkstk_darwin
  Referenced from: /Applications/RenderTune.app/Contents/Resources/ffmpeg
  Expected in: /usr/lib/libSystem.B.dylib

    at makeError (/Applications/Render…eca/lib/error.js:59)
    at handlePromise (/Applications/Render…/execa/index.js:114)
    at async file:/Applicat…js/newindex.js:1323


  


  These files will render fine on windows/linux and recent mac versions. In order to package ffmpeg in my electron app on mac computers I had to build a custom sandboxed version with no dynamically linked libraries. I have a .sh file that automatically downloads ffmpeg and builds it with all the necessary flags for mac computers.
https://github.com/MartinBarker/RenderTune/blob/master/buildffmpeg.sh
Inside this .sh file is where I compile ffmpeg using these flags :

  


  ./configure \
    --pkgconfigdir="$WORKSPACE/lib/pkgconfig" \
    --prefix=${WORKSPACE} \
    --pkg-config-flags="--static" \
    --extra-cflags="-I$WORKSPACE/include -mmacosx-version-min=${MACOS_MIN}" \
    --extra-ldflags="-L$WORKSPACE/lib -mmacosx-version-min=${MACOS_MIN}" \
    --extra-libs="-lpthread -lm" \
        --enable-static \
        --disable-securetransport \
        --disable-debug \
        --disable-shared \
        --disable-ffplay \
        --disable-lzma \
        --disable-doc \
        --enable-version3 \
        --enable-pthreads \
        --enable-runtime-cpudetect \
        --enable-avfilter \
        --enable-filters \
        --disable-libxcb \
        --enable-gpl \
        --enable-nonfree \
        --disable-libass \
        --enable-libfdk-aac \
        --enable-libmp3lame \
        --enable-libx264 


  


  If I try to run this script in my High Sierra VM, it fails with this message :

  


  Unknown option "-extra-libs=-lpthread"

  


  if I remove that flag it fails with a different message :

  


  Unknown option "--enable-static"

  


  I need this flag in order to release my electron app on the mac apple store, can anyone help me compile a static version of ffmpeg that works on old versions like High Sierra 10.13 as well as works on modern mac os systems ?

  


• High quality compression with cuda

  6 février 2020, par Alex

  I want to convert

  ffmpeg -i input.mp4 -maxrate 63317762 -bufsize 63317762 -map_metadata -1 -vcodec libx265 -c:a copy -crf 28 -color_range 2 output.mp4

  into a command that uses cuda to speed the conversion process.

  I tried

  ffmpeg.exe -hwaccel cuvid -i input.mp4 -pix_fmt p010le -c:v hevc_nvenc -preset slow -rc vbr_hq -b:v 6M -maxrate:v 63317762 -bufsize:v 63317762 -c:a aac output.mp4

  And it didn’t work.

  I tried

  ffmpeg.exe -hwaccel cuvid -i input.mp4 -c:v hevc_nvenc -preset slow -rc vbr_hq -b:v 6M -maxrate:v 63317762 -bufsize:v 63317762 -c:a aac output.mp4

  and it worked, yet it set the bitrate for video to 6M.

  I want ffmpeg to guess it based on content up to 63317762 bytes. Like a good tradeoff between quality and bitrate but below 63317762 bytes but also without visible block building and blurryness.

  And with cuda.

  Which command does that ?