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• How to get rtmpte video streaming url / how to download rtmpe video streaming [on hold]

  22 décembre 2015, par Jeanluca

  I would like to download a video stream

  I try to retrieve the url of this video stream (from jwplayer)

  I use Media sniffer to get the url of this video, I get this :
  after every 40 seconds I get url :

  capture : Media Sniffer

  http://jwpltx.com/v1/jwplayer6/ping.gif ?h=-1642491063&tv=70&n=0231308063450995&aid=jCLHImWKEeSGUxLddj37mA&e=s&i=0&ifd=0&pv=7.2.4&m=1&d=0&t=&vs=3&ed=2&ph=1&ps=4&l=4&ff=4746&q=32&pp=flash_rtmp&sdk=0&emi=az1z36eegar0&pli=dp3y8o9hj8n0&mu=http ://www.alphorm.com/formation/rtmpte :/rtmp.alphorm.eu/cfx/st/mp4:FR_237/FR_237_01_00.mp4?Expires=1450841655&Signature=s-eWpUF1pFxlm31kZQrEClqaFL3O9YbJ0vE-k94kIlWv9dVEX8G0FbPGI7zcgXklH3GrwxkK8iXlOfOXE481GzJca1T4NAsQ0R38SJ6RKU-sR1C6fQ5-nLdNtO0EB3A59SMcQx9ueBou-sFOgVmEIPTd1Hvpht67JQbYWFlBkLw_&Key-Pair-Id=APKAJF2PMCJPGKXG2GEA&eb=0&pu=http://www.alphorm.com/formation/formation-en-ligne-red-hat-rh124&id=&pt=Red Hat RH124

• Revision 30295 : Amélioration de l’encodage multiple

  28 juillet 2009, par kent1@… — Log

  Amélioration de l’encodage multiple

• Playing sound from a video using FFmpeg and SDL_QueueAudio results in high pitched audio

  26 septembre 2021, par plieblang

  I'm trying to play audio from an mp4 file using SDL2 and FFmpeg, and using SDL_QueueAudio seems much easier than setting up a callback.

  



  All solutions I've found, whether here or in the dranger tutorials, are deprecated or use callbacks. I tried browsing all questions with both the ffmpeg and sdl tags (there aren't many), to no avail. I tried converting the dranger tutorial to use non-deprecated calls but ran into the same problem. I'm using C, FFmpeg 4.1 and SDL 2.0.9.

  



  This is the setup for AVCodecContext and AVCodec :

  



      int audioStream = -1;
    for (i = 0; i < formatContext->nb_streams; i++) {
        if (audioStream < 0 && formatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
            audioStream = i;
        }
    }

    AVCodecParameters *audioParams = formatContext->streams[audioStream]->codecpar;

    AVCodec *audioCodec = avcodec_find_decoder(audioParams->codec_id);

    AVCodecContext *audioCodecCtx = avcodec_alloc_context3(NULL);
    avcodec_open2(audioCodecCtx, audioCodec, NULL);

    SDL_Init(SDL_INIT_AUDIO)

    SDL_AudioSpec desired, obtained;
    SDL_zero(desired);
    SDL_zero(obtained);
    desired.freq = audioCodecCtx->sample_rate;
    desired.format = AUDIO_F32SYS;
    desired.channels = audioCodecCtx->channels;
    desired.silence = 0;
    desired.samples = AUDIO_BUFFER_SIZE;

    SDL_AudioDeviceID audioDevice = SDL_OpenAudioDevice(NULL, 0, &desired, &obtained, SDL_AUDIO_ALLOW_ANY_CHANGE);


  



  This is the main packet decoding loop :

  



      while (av_read_frame(formatContext, &packet) >= 0) {
        if (packet.stream_index == audioStream) {
            if (!avcodec_send_packet(audioCodecCtx, &packet)) {
                avcodec_receive_frame(audioCodecCtx, audioFrame);
                SDL_QueueAudio(audioDevice, audioFrame->data[0], audioFrame->linesize[0]);
            }
        }
    }


  



  The audio plays at the correct speed but at a much higher pitch than what it actually is. I would like it to sound the same as in any media player.
  
Edit : I just realized the test video has stereo audio but I'm only queueing audioFrame.data[0], which I assume means I'm only playing one channel. I tried queueing audioFrame.data[1] which has data as well but it did not solve the problem. Am I correct and if so, how do I play both channels ?