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• Can't open encoder when use libavcodec

  1er novembre 2013, par liuyanghejerry

  I'm using libavcodec, version 9.7, to write a simple demo, almost exactly like example in official example.

  However, I can't open encoder. Also, av_opt_set(context->priv_data, "preset", "slow", 0) always leads to crush.

  This is my code :

  // other code...
  
  int ret = 0;
  
  avcodec_register_all();
  
  AVCodec* codec = NULL;
  
  AVCodecContext* context = NULL;
  
  AVFrame* frame = NULL;
  
  uint8_t endcode[] = { 0, 0, 1, 0xb7 };
  
  codec = avcodec_find_encoder(AV_CODEC_ID_H264);
  
  if(!codec){
  
      qDebug()<<"cannot find encoder";
  
      return;
  
  }
  
  qDebug()<<"encoder found";
  
  
  
  context = avcodec_alloc_context3(codec);
  
  if(!context){
  
      qDebug()<<"cannot alloc context";
  
      return;
  
  }
  
  qDebug()<<"context allocted";
  
  
  
  context->bit_rate = 400000;
  
  /* resolution must be a multiple of two */
  
  context->width = 352;
  
  context->height = 288;
  
  /* frames per second */
  
  context->time_base= (AVRational){1,25};
  
  context->gop_size = 10; /* emit one intra frame every ten frames */
  
  context->max_b_frames=1;
  
  context->pix_fmt = AV_PIX_FMT_YUV420P;
  
  qDebug()<<"context init";
  
  
  
  // av_opt_set(context->priv_data, "preset", "slow", 0); // this will crush
  
  AVDictionary *d = NULL;
  
  av_dict_set(&d, "preset", "ultrafast",0); // this won't
  
  
  
  ret = avcodec_open2(context, codec, &d);
  
  if ( ret < 0) {
  
      qDebug()<<"cannot open codec"</ other code...

  This outputs :

  encoder found

  context allocted

  context init

  cannot open codec -22

  [libx264 @ 0340B340] [IMGUTILS @ 0028FC34] Picture size 0x10 is invalid

  [libx264 @ 0340B340] ignoring invalid width/height values

  [libx264 @ 0340B340] Specified pix_fmt is not supported

  I don't think the width/height is invalid and format there either. I have no idea what's wrong here.

  Any help. plz ?

• fate/webp : add test for lossy compression.

  26 juin 2016, par Martin Vignali

  fate/webp : add test for lossy compression.
  the result of ffmpeg decoding is binary exact with the yuv output of
  
  official decoder (dwebp)
  Signed-off-by : James Almer <jamrial@gmail.com>
  

  • [DH] tests/fate/image.mak
  • [DH] tests/ref/fate/webp-rgb-lossy-q80
  • [DH] tests/ref/fate/webp-rgba-lossy-q80

• Concatenate multiple video php ffmpeg

  3 mai 2017, par Angus Simons

  I have multiple files that are already been encoded (they have the same format and size) I would like to concatenate on a single video (that already exist and has to be overwritten).

  Following the official FAQ Documentation I should use demuxer

  FFmpeg has a concat demuxer which you can use when you want to avoid a
  re-encode and your format doesn’t support file level concatenation.

  The problem is that I should use a .txt file with a list of files using this command line

  ffmpeg -f concat -safe 0 -i mylist.txt -c copy output

  where mylist.txt should be :

  file '/path/to/file1'
  
  file '/path/to/file2'
  
  file '/path/to/file3'

  How can I do with PHP ?

  ---

  Also tried with concat protocol

  I tried using also the concat protocol that re-encode videos with these lines of code :

  $cli = FFMPEG.' -y -i \'concat:';
  
  
  
  foreach ($data as $key => $media) {
  
    $tmpFilename = $media['id'];
  
    $tmpPath = $storePath.'/tmp/'.$tmpFilename.'.mp4';
  
  
  
    if ($key != ($dataLenght - 1)) {
  
      $cli .= $tmpPath.'|';
  
    } else {
  
      $cli .= $tmpPath.'\'';
  
    }
  
  }
  
  
  
  $cli .= ' -c copy '.$export;
  
  exec($cli);

  that generate this command line :

  /usr/local/bin/ffmpeg -i 'concat:/USER/storage/app/public/video/sessions/590916f0d122b/tmp/1493768472144.mp4|/USER/storage/app/public/video/sessions/590916f0d122b/tmp/1493767926114.mp4|/USER/storage/app/public/video/sessions/590916f0d122b/tmp/1493771107551.mp4|/USER/storage/app/public/video/sessions/590916f0d122b/tmp/1493771114598.mp4' -c:v libx264  /USER/storage/app/public/video/sessions/590916f0d122b/tmp_video_session.mp4

  but I got this error :

  [mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fc8aa800000] Found duplicated MOOV Atom. Skipped it