Recherche avancée

Sur d’autres sites (6898)

• Use FFmpeg to generate a movie with alpha channel from separate video and fill movies ?

  25 octobre 2017, par jeffpatt

  I have two movies : input_v.mp4 and input_k.mp4. input_v is the video fill, input_k is a black and white matte for keying.

  I want to use FFmpeg to create output.mov in the Avid DNXHD codec, with input_v as the fill (RGB) video and the alpha (A) built from the luma values of input_k.

  Is this possible ?

• how to add reference movie into ffmpeg psnr filter in codes (computing psnr)

  15 octobre 2016, par user1317278

  I just want to find out how to use the psnr filter in ffmpeg in codes.

  I have followed the codes stated in https://ffmpeg.org/ffmpeg-filters.html#psnr :

  sprintf(args, "movie=ref_movie.avi [main];[main][ref] psnr=\"stats_file=stats.log\" [out]");
  
  err = avfilter_graph_create_filter(&psnrCtx,  psnrFilter, "psnr", args, NULL, m_filterGraph);
  
  if ( err < 0 ) {
  
      avfilter_graph_free(&m_filterGraph);
  
      m_filterGraph = NULL;
  
      return false; }

  But the error message return to me :

  Option 'movie' not found

  I also try this :

  sprintf(args, "stats_file=stats.log");
  
  err = avfilter_graph_create_filter(&psnrCtx,  psnrFilter, "psnr", args, NULL, m_filterGraph);
  
  if ( err < 0 ) {
  
     avfilter_graph_free(&m_filterGraph);
  
     m_filterGraph = NULL;
  
     return false; }
  
  err = avfilter_link(last_ctx, 0, psnrCtx, 0);
  
  if ( err < 0 ) {
  
     avfilter_graph_free(&m_filterGraph);
  
     m_filterGraph = NULL;
  
     return false;}
  
  
  
  ...  
  
  err = avfilter_graph_config(m_filterGraph, NULL);
  
  if ( err < 0 ) {
  
     avfilter_graph_free(&m_filterGraph);
  
     m_filterGraph = NULL;
  
     return false;
  
  }

  but the error message return to me :

  Input pad "reference" with type video of the filter instance "psnr" of psnr not connected to any source

  I search psnr filter in codes but there is not much information about it. Can anyone help on this ?

• FFMPEG convert .avi into playable iOS movie mp4

  8 janvier 2016, par Julien Klindt

  I’m trying to convert an avi file which is h264 encoded baseline4.0 to a new h264 mpeg file that is encoded with baseline3.

  The file original file is not playable on any iOS device, due to baseline4.0 (I think ?)

  I’m using this wrapper class here https://github.com/OpenWatch/FFmpegWrapper

  but actually I have no clue how to set baseline. I can convert to mpeg4, but it seems that defaults everytime to baseline4.0.

  I tried to set it on the AVCodecContext

  AVCodecContext *outputCodecContext = outputStream->codec;
  
  outputCodecContext->level = 31;
  
  outputCodecContext->profile = FF_PROFILE_H264_BASELINE;

  but this has no effect.

  Perhaps anybody has a clue, or has a better FFMPEGWrapper.

  Specs from original video :