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• arm : implement x264_predict_4x4_v_armv6

  13 mars 2014, par Janne Grunau

  arm : implement x264_predict_4x4_v_armv6
  Alone probably not worth it but allows use of predict_4x4_dc|h_armv6
  
  in intra_sad|satd_x3_4x4_neon.
  

  • [DH] common/arm/predict-a.S
  • [DH] common/arm/predict-c.c
  • [DH] common/arm/predict.h
  • [DH] common/pixel.c

• avfilter/vf_removegrain : replace qsort with AV_QSORT

  25 octobre 2015, par Ganesh Ajjanagadde

  avfilter/vf_removegrain : replace qsort with AV_QSORT
  filter_slice calls qsort, so qsort is in a performance critical
  
  position. AV_QSORT is substantially faster due to the inlining of the
  
  comparison callback. Thus, the increase in performance is worth the
  
  increase in binary size.
  Sample benchmark (x86-64, Haswell, GNU/Linux),
  
  filter-removegrain-mode-02 (from FATE)
  
  new :
  
    24060 decicycles in qsort,       1 runs,      0 skips
  
    15690 decicycles in qsort,       2 runs,      0 skips
  
     9307 decicycles in qsort,       4 runs,      0 skips
  
     5572 decicycles in qsort,       8 runs,      0 skips
  
     3485 decicycles in qsort,      16 runs,      0 skips
  
     2517 decicycles in qsort,      32 runs,      0 skips
  
     1979 decicycles in qsort,      64 runs,      0 skips
  
     1911 decicycles in qsort,     128 runs,      0 skips
  
     1568 decicycles in qsort,     256 runs,      0 skips
  
     1596 decicycles in qsort,     512 runs,      0 skips
  
     1614 decicycles in qsort,    1024 runs,      0 skips
  
     1874 decicycles in qsort,    2046 runs,      2 skips
  
     2186 decicycles in qsort,    4094 runs,      2 skips
  old :
  
   246960 decicycles in qsort,       1 runs,      0 skips
  
   135765 decicycles in qsort,       2 runs,      0 skips
  
    70920 decicycles in qsort,       4 runs,      0 skips
  
    37710 decicycles in qsort,       8 runs,      0 skips
  
    20831 decicycles in qsort,      16 runs,      0 skips
  
    12225 decicycles in qsort,      32 runs,      0 skips
  
     8083 decicycles in qsort,      64 runs,      0 skips
  
     6270 decicycles in qsort,     128 runs,      0 skips
  
     5321 decicycles in qsort,     256 runs,      0 skips
  
     4860 decicycles in qsort,     512 runs,      0 skips
  
     4424 decicycles in qsort,    1024 runs,      0 skips
  
     4191 decicycles in qsort,    2046 runs,      2 skips
  
     4934 decicycles in qsort,    4094 runs,      2 skips
  Reviewed-by : Michael Niedermayer <michael@niedermayer.cc>
  
  Signed-off-by : Ganesh Ajjanagadde <gajjanagadde@gmail.com>
  

  • [DH] libavfilter/vf_removegrain.c

• Stop encoding a video from piped video and directshow audio data

  9 avril 2023, par obscure

  Via node.js I'm spawning a FFmpeg process which generates a video using jpeg images received from a node.js stream. Additionally it records audio from a directshow device.

  


  const child = require("child_process");
const stream = require("stream");
let inputStream = new stream.PassThrough();
let ffmpeg = child.spawn("ffmpeg.exe", [
    "-f", "image2pipe", "-r", "24", "-fflags", "nobuffer",
    "-i", "pipe:0",
    "-f", "dshow",
    "-sample_rate",
    "48000",
    "-i", 'audio="Microphone"',
    "-acodec",
    "pcm_s16le",
    "-ac", "2",
    "-ar", "48000",
    "-vcodec", "libx264",
    "-crf", "10",
    "-preset", "veryfast",
    "-framerate", "1",
    "output.mkv"
]);

inputStream.pipe(ffmpeg.stdin);


  


  The problem is, if I later stop sending images down the pipe

  


  inputStream.end();


  


  to ultimately stop FFmpeg from encoding the video, it does not stop - I guess because it's still grabbing audio data from the directshow device.

  


  After digging through the FFmpeg manual I've found the -shortest output options which should :

  


  


  ...Finish encoding when the shortest output stream ends...

  


  


  So upon adding the option e.g.

  


  ...
    "-preset", "veryfast",
    "-framerate", "1",
    "-shortest"
    "output.mkv"
]);


  


  it indeed stops encoding but it's happening too fast.

  


  So a video worth 10 seconds of data just has 5 seconds of audio and from second 5 - 10 there's just silence. I assume it's happening because it doesn't drain the rest of the audio buffer before stopping.

  


  How can I stop encoding the output from the video and the audio data, while keeping all the data up to the point I've triggered the 'stop' ?