Recherche avancée

Sur d’autres sites (11418)

• avformat/yop : Use av_packet_move_ref() for packet ownership transfer

  21 mars 2020, par Andreas Rheinhardt

  avformat/yop : Use av_packet_move_ref() for packet ownership transfer
  Also return 0 after successfully reading a packet.
  Reviewed-by : Anton Khirnov <anton@khirnov.net>
  
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavformat/yop.c

• What's the replacement for the avcodec_thread_init ?

  7 mai 2015, par Nyaruko

  I am using ffmpeg to encode/decode videos.
  I used a old version in the past, but recently I switched a new version and found that many ffmpeg functions are non-longer in use.

  Here is my old code :

   pCodecCtx=pVideoStream->codec;
  
     pCodecCtx->codec_id = pOutputFormat->video_codec;
  
     pCodecCtx->codec_type = ffmpeg::AVMEDIA_TYPE_VIDEO;
  
  
  
     pCodecCtx->bit_rate = Bitrate;
  
     pCodecCtx->width = getWidth();
  
     pCodecCtx->height = getHeight();
  
     pCodecCtx->time_base.den = fps;
  
     pCodecCtx->time_base.num = 1;
  
     pCodecCtx->gop_size = Gop;
  
     pCodecCtx->pix_fmt = ffmpeg::PIX_FMT_YUV420P;
  
  
  
  
  
     avcodec_thread_init(pCodecCtx, 10);
  
  
  
     //if (c->codec_id == CODEC_ID_MPEG2VIDEO)
  
     //{
  
        //c->max_b_frames = 2;  // just for testing, we also add B frames
  
     //}
  
  
  
     // some formats want stream headers to be separate
  
     if(pFormatCtx->oformat->flags & AVFMT_GLOBALHEADER)
  
        pCodecCtx->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
  
  
  
  
     if (av_set_parameters(pFormatCtx, NULL) < 0)
  
     {
  
        printf("Invalid output format parameters\n");
  
        return false;
  
     }
  
  
  
     ffmpeg::dump_format(pFormatCtx, 0, fileName.toStdString().c_str(), 1);
  
  
  
     // open_video
  
     // find the video encoder
  
     pCodec = avcodec_find_encoder(pCodecCtx->codec_id);
  
     if (!pCodec)
  
     {
  
        printf("codec not found\n");
  
        return false;
  
     }
  
     // open the codec
  
     if (avcodec_open(pCodecCtx, pCodec) < 0)
  
     {
  
        printf("could not open codec\n");
  
        return false;
  
     }
  
  
  
     // Allocate memory for output
  
     if(!initOutputBuf())
  
     {
  
        printf("Can't allocate memory for output bitstream\n");
  
        return false;
  
     }
  
  
  
     // Allocate the YUV frame
  
     if(!initFrame())
  
     {
  
        printf("Can't init frame\n");
  
        return false;
  
     }
  
  
  
     if (url_fopen(&pFormatCtx->pb, fileName.toStdString().c_str(), URL_WRONLY) < 0)
  
     {
  
        printf( "Could not open '%s'\n", fileName.toStdString().c_str());
  
        return false;
  
     }
  
  
  
     av_write_header(pFormatCtx);

  Here, avcodec_thread_init is no-longer in use and I cannot find anyhints about what function I should use to replace it ? Any ideas ?

• Assistance required with filter graph construction(fast motion between times)

  6 janvier 2023, par D-MAN

  I am trying to re-create the following video, using ffmpeg.
https://youtu.be/eVQ9ysp0Pj0. "please check 0.19 minute for examples"
I have the following line of code which has most of the elements, except the part where is applies fast motion for 1s at certain outputs([vfr1][vfr2][vfr3])/times. currently it is only setpts=0.5*PTS[vboom] for the entire length of the video.

  


  exe = "-i " + file + " -i " + frame + " -i " + framestart + " -i " + frameEnd + " -i " + audioOverlay + " -filter_complex \"[0:v]pad="+mVideoWidth+":"+mVideoHeight+":576:0[vpad]; [vpad][1]overlay[vframed]; [vframed]split=3[vfr1][vfr2][vfr3]; [vfr1]reverse[vrev]; [vfr2][vrev][vfr3]concat=n=3,setpts=0.5*PTS[vboom]; [vboom][2]overlay=enable='lte(t,2)'[vpreout]; [vpreout][3]overlay=enable='gte(t,"+msec+"*3*0.5-2)' \" -map 4:a -b:v 8000k -shortest -preset ultrafast -crf 23 " + file2.getAbsolutePath();

  


  i have tried the following code snippets in various sections of the filter graph, with no luck !

  


  //[0:v]trim=0:2,setpts=PTS-STARTPTS[v1] ;[0:v]trim=2:5,setpts=2*(PTS-STARTPTS)[v2] ;[0:v]trim=5,setpts=PTS-STARTPTS[v3] ;
//[0:v]trim=0:10,setpts=PTS-STARTPTS[vfr1] ;[0:v]trim=10:30,setpts=PTS-STARTPTS[vfr2] ;[0:v]trim=start=30,setpts=PTS-STARTPTS[vfr3] ;
//[0:v]trim=2:3,setpts=0.75*(PTS-STARTPTS) ; [0:v]trim=4:5,setpts=0.75*(PTS-STARTPTS) ; [0:v]trim=7:8,setpts=0.75*(PTS-STARTPTS) ;
//[0:v]select='between(t,1,4)+between(t,4,6)',setpts=0.87*PTS ;