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• Why does x264 keep giving me "command not found" error on my Mac ? [closed]

  2 juillet 2021, par hd-dvd

  I just installed x264 via Homebrew on my Mac running MacOS 11.4 Big Sur. I'm trying to encode a video but I can't get x264 to run properly.

  


  This is the command I am running in the Terminal :

  


  x264 --bitrate 25000 --preset veryslow --bluray-compat --tune film --vbv-maxrate 40000 --vbv-bufsize 30000 --level 4.1 --keyint 30 --open-gop --slices 4 --fake-interlaced --colorprim "bt709" --transfer "bt709" --colormatrix "bt709" --sar 1:1 --pass 1 -o out.264 in.mp4

  


  and this is what it outputs :

  


  bash: x264 --bitrate 25000 --preset veryslow: command not found

  


  If I delete the --preset part then it just gets hung up on some other part, like --tune.

  


  I have tried brew doctor and there are no errors.

  


  If I just run x264 then it gives me x264 [error]: No input file. Run x264 --help for a list of options. so it seems as if x264 is installed. I don't know where to begin troubleshooting this but I'd like to get it to work.

  


  If I simplify the command way down to x264 -o out.264 in.mp4 then I get :

  


  avs [error]: failed to load avisynth
raw [error]: raw input requires a resolution.
x264 [error]: could not open input file `in.mp4' via any method!


  


  I would greatly appreciate some pointers on how to get this working.

  


• ffmpeg (IMAGE THUMBNAIL 1 frame) how to "choose" compression quality when we use -vframes 1 (how to do like convert -quality 60....)

  25 juillet 2021, par jini

  • PRE-CONTEXT : with ImageMagick, I'm use to do convert -quality 60 1.jpg 1.webp here "quality 60" affect the final size of the output

  


  • CONTEXT : create a poster.webp OR poster.jpg of a movie.mp4

  


  • QUESTION : how can we "achieve" the same compression level choice with ffmpeg when we want 1 frame

  


  • WHAT I TRIED [1] :

  


  ffmpeg -i movie.mp4 -vframes 1 -qmin 0 -qmax 1  0.webp

  


  and ffmpeg -i movie.mp4 -vframes 1 -qmin 50 -qmax 51 50.webp

  


  ==>> both gives the exact same size for the output.

  


  • WHAT I TRIED [2] :

  


  ffmpeg -i movie.mp4 -vframes 1 -b:v 9k bv9k.webp

  


  and ffmpeg -i movie.mp4 -vframes 1 -b:v 1k bv1k.webp

  


  ==>> both gives the exact same size for the output.

  


  what I'm I missing or miss using here ?

  


  Thanks

  


• lavc/mediacodecdec : set codec profile and level from extradata for H264+HEVC

  13 décembre 2021, par sfan5

  lavc/mediacodecdec : set codec profile and level from extradata for H264+HEVC
  This value is later passed to MediaCodec and checked at decoder init.
  
  Notably decoding of 10-bit streams before this commit would "work" without
  
  returning errors but only return garbage output (on most Android devices).
  

  • [DH] libavcodec/mediacodecdec.c