Recherche avancée

Sur d’autres sites (11563)

• How to extract the singer's voice from a song using FFMPEG ?

  8 mars 2023, par x27x

  I tried with this command :

  


  ffmpeg -i song.mp3 -af pan="stereo|c0=c0|c1=-1*c1" -ac 1 karaoke.mp3

  


  But the output was the music without the singer's voice

  


   :) Is this possible with FFMPEG ?
Is there an alternative ?

  


• How does winget set permanent aliases ?

  9 septembre 2023, par ninbura

  When I install something like ffmpeg with winget, it sets permanent aliases for ffmpeg, ffplay, & ffprobe.

  


  winget install gyan.ffmpeg


  


  It doesn't look like it's adding anything to my path environment variable. If I use the Set-Alias utility said alias is ephemeral, only lasting until the end of the current session. Eventually I found that I can use my $profile to denote a list of aliases that instantiate every time I launch my shell.

  


  Does winget do the same thing just with a different "profile" file ?

  


• How to save data of packet.data in ffmpeg using c language ?

  10 juin 2015, par patrick

  I’m try to build an app in c that extract audio from video and save it as audio file. I write the below code. I’m able to extract the audio but now the problem is how to save it. Thanks in advance.

  My code is :

  int main(int argc, char *argv[]) {
  
  AVFormatContext *pFormatCtx = NULL;
  
  int             i;
  
  AVCodecContext  *pCodecCtx = NULL;
  
  AVCodec         *pCodec = NULL;
  
  AVFrame         *pFrame = NULL; 
  
  AVPacket        packet;
  
  
  
  AVDictionary    *optionsDict = NULL;
  
  
  
  if(argc < 2) {
  
  printf("Please provide a movie file\n");
  
  return -1;
  
  }
  
  av_register_all();
  
  if(avformat_open_input(&pFormatCtx, argv[1], NULL, NULL)!=0)
  
  return -1; 
  
  
  
  if(avformat_find_stream_info(pFormatCtx, NULL)<0)
  
  return -1; 
  
  
  
  av_dump_format(pFormatCtx, 0, argv[1], 0);
  
  
  
  int audioStream=-1;
  
  for(i=0; inb_streams; i++)
  
      if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO) {
  
          audioStream=i;
  
          break;
  
      }
  
  if(audioStream==-1)
  
  return -1; 
  
  
  
  pCodecCtx=pFormatCtx->streams[audioStream]->codec;
  
  
  
  pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
  
  if(pCodec==NULL) {
  
      fprintf(stderr, "Unsupported codec!\n");
  
      return -1; // Codec not found
  
  }
  
  
  
  if(avcodec_open2(pCodecCtx, pCodec, &optionsDict)<0)
  
  return -1; 
  
  
  
  pFrame=avcodec_alloc_frame();
  
  packet.data = NULL;
  
  packet.size = 0;
  
  
  
  while(av_read_frame(pFormatCtx, &packet)>=0) {
  
      int got_frame = 0;
  
      int ret = avcodec_decode_audio4(pCodecCtx, pFrame, &got_frame, &packet);
  
      if(got_frame && packet.stream_index==audioStream) {
  
          //save result but how???
  
      }
  
      av_free_packet(&packet);
  
  }
  
  av_free(pFrame);
  
  avcodec_close(pCodecCtx);
  
  avformat_close_input(&pFormatCtx);
  
  return 0;
  
  }