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• Truncated prog_index.m3u8 in fluent-ffmpeg

  10 juillet 2020, par Hassnain Alvi

  I am creating a master playlist using fluent FFmpeg but the result prog_index.m3u8 contains last few entries it doesn't include full playlist data

  


  Here is the code for generating playlist

  


  const bitrate64 = ffmpeg("file.mp3").audioBitrate('64k');
    bitrate64.outputOptions([
        '-preset slow',
    '-g 48',
    "-map", "0:0",
        '-hls_time 6',
        '-master_pl_name master.m3u8',
        '-hls_segment_filename 64k/fileSequence%d.ts'
    ])
    .output('./64k/prog_index.m3u8')
    .on('progress', function(progress) {
        console.log('Processing 64k bitrate: ' + progress.percent + '% done')
    })  
    .on('end', function(err, stdout, stderr) {
        console.log('Finished processing 64k bitrate!')
    })
    .run() 


  


  Here is the output from prog_index.m3u8

  


  #EXTM3U
#EXT-X-VERSION:3
#EXT-X-TARGETDURATION:6
#EXT-X-MEDIA-SEQUENCE:1221
#EXTINF:5.990756,
fileSequence1221.ts
#EXTINF:6.013967,
fileSequence1222.ts
#EXTINF:5.990744,
fileSequence1223.ts
#EXTINF:6.013967,
fileSequence1224.ts
#EXTINF:5.953600,
fileSequence1225.ts
#EXT-X-ENDLIST


  


  when I run this command manually I get full index file but not with FFmpe. All .ts sequence files are correctly generated but. prog_index is not updated accordingly

  


  Can anyone tell me what I am doing wrong here ?

  


• ffmpeg concatenate a large number of videos with different codecs and resolutions

  21 avril 2024, par Paul H

  The videos I am trying to concatenate can have different technical metadata, like codec, resolution, etc. So I wrote a filtergraph that works for my purposes. My complete command can look like this :

  



  ffmpeg -i "vid1.mp4" -i "vid2.mp4" -i "vid3.mp4" -filter_complex_script "filtergraph.txt" -map "[outv]" -map "[outa]" -c:v libx264 -r 60 -preset medium -crf 24 -c:a aac -b:a 160k "output.mp4"


  



  And "filtergraph.txt" looks like this (autogenerated by my own script before). I have the filters to change all input resolutions to Full HD. (Newlines in the following snippet are just introduced for readability, they are not contained in my filtergraph.txt)

  



  [0:v]scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2,setsar=1[v0];
[1:v]scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2,setsar=1[v1];
[2:v]scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2,setsar=1[v2];
[v0][0:a][v1][1:a][v2][2:a]concat=n=3:v=1:a=1[outv][outa]


  



  Now in this case, it works, I have the three source videos, they can have different resolutions, codecs or even different framerates - they are all combinded into one Full HD 60 FPS output video.

  



  The problem is, that I want to concatenate a large number of video files and get the error, that the command contains too many characters for cmd. That's why I already put the filtergraph to a seperate file and read it using -filter_complex_script which works.

  



  But it can still get too long if I have a few hundred source files that I want to concat.

  



  As far as I tested it, I can't use -f concat -i listOfFiles.txt because every source file would have to be in the same codec, resolution etc then, and I could not use the filtergraph for scaling due to the fact that ffmpeg would try to concat before demuxed output goes into filter.

  



  So, how could I concat hundreds of videos while resizing them all to Full HD and applying the other filters, but keep the cmd line short ?

  



  Is there something similar to -filter_complex_script but for input files ? Or will I have to encode each source video to my desired target format first and then concat them with stream copy ?

  


• How to encode with ffmpeg if number of images smaller than GOP size

  10 avril 2013, par theateist

  The code bellow creates mp4 video file from jpeg images. When number of images is greater than GOP size the encoding success and after 10th image gotPacket that returned by avcodec_encode_video2 is > 0.

  BUT when number of images is smaller than GOP size gotPacket is always = 0 and therefore no images written to the file.

  My guess is that avcodec_encode_video2 allocates buffer with length equals to GOP size and until it won't be full gotPacket will be 0.

  My question is how to force avcodec_encode_video2 to encode even if it's buffer is not full ?

  ...
  
  _outStream->codec.gop_size = 10;
  
  _outStream->codec.keyint_min = 10;
  
  ...
  
  
  
  AVFrame* frame = getFrame();
  
  
  
  
  
  AVPacket packet;
  
  av_init_packet(&packet);
  
  packet.data = NULL;
  
  packet.size = 0;
  
  
  
  int gotPacket = 0;
  
  if (avcodec_encode_video2(_outStream->codec, &packet, frame, &gotPacket) < 0)
  
      throw std::runtime_error("failed to encode frame");
  
  
  
  if (gotPacket)
  
  {
  
      ...
  
      if (av_write_frame(_outContainer.get(), &packet) < 0)
  
          throw std::runtime_error("failed to write frame");      
  
      av_free_packet(&packet);
  
  }