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• Revision febdebf27a : remove remaining references to XMA the bulk of the functionality was removed in

  10 août 2014, par James Zern

  Changed Paths :
   Modify /usage.dox

  
   Modify /vpx/src/vpx_decoder.c

  
   Modify /vpx/src/vpx_encoder.c

  
   Modify /vpx/vpx_codec.h

  
   Modify /vpx/vpx_decoder.h

  
   Modify /vpx/vpx_encoder.h

  
  
  remove remaining references to XMA

  the bulk of the functionality was removed in :
  a42b5c2 Removing legacy XMA features from libvpx.

  BUG=840

  Change-Id : I8ca51d6aa76028f36d0eb1a15d2f2e3161e12ea4

• Output a video to a file

  3 novembre 2011, par EagleEye

  I am working on a very CPU intensive legacy application on windows which captures video frames from camera and displays it on the screen. Now I need to add a feature to it to save this video feed to an output file. And I have a raw image data as an input. I need to make this process as efficient as possible so that it doesn't affect the performance of my application.

  So what are the best available API's in C++ that I can use to create an output video file. And moreover what should be the most efficient encoding format that I must use so that I get the maximum throughput. Also I may have to use some compression techniques. So what should be the best approach.

  Moreover can I use GPU acceleration for this process and how ?

  Uptil now I have encountered following tools that I may use :

  1. OpenCV
  2. Microsoft Media Foundation LIbrary or DirectShow
  3. ffmpeg

• av_write_header - Error with sample format

  18 mai 2021, par szymek349

  I'm writing program with libav/ffmpeg to download internet radio stream and play it on soundcard with alsa.

  


  I've managed to download stream and extract packet and frame.

  


  I'm having problem with av_write_header() function which (according to this https://www.ffmpeg.org/doxygen/3.2/group__lavf__encoding.html#details) I must call. It crashes and gives me the following error :

  


  [alsa @ 0x55d7ba32e580] sample format 0x15001 is not supported

  


  Number 0x15001 is 86017 in decimal, which is index in enum AVCodecID of MP3 format(AV_CODEC_ID_MP3) used by this stream. The sample format has index 3. I can't figure out why libav parses the header wrong.

  


  Here is a part of my code that is responsible for configuring output :

  


      avdevice_register_all();

    AVOutputFormat *output = av_guess_format("alsa",NULL,NULL);

    AVFormatContext *outputFormatContext = avformat_alloc_context();
    outputFormatContext->oformat = output;
    outputFormatContext->flags = AVFMT_NOFILE;

    AVStream *stream = avformat_new_stream(outputFormatContext,NULL);

    AVCodecParameters *oCodecParameters = avcodec_parameters_alloc();

    ret = avcodec_parameters_copy(oCodecParameters,iCodecParameters);
    if(ret < 0){
        printf("avformat_parameters_copy\n");
        exit(0);
    }

    stream->codecpar = oCodecParameters;

    if(avformat_write_header(outputFormatContext,NULL)<0){
        dumpParameters(stream->codecpar);
        printf("avformat_write_header\n");
        exit(0);
    }


  


  The full code is here : https://github.com/szymonbarszcz99/C-internet-radio