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• Clipping audio problem on ffmpeg live stream

  20 mars 2019, par Ivan Bombash Stokic

  in 30-40% of the live stream i get some king of distortion or clipping in the streamed audio and i have no idea why, is is only because low hardware performance maybe ? I am running the stream on a Raspberry pi 3b+ CPU usage while streaming from 25 to 30% Ram usage 28% , storage device is a USB pen drive.

  Here is the code :

  ffmpeg -re -f alsa -i default -re -stream_loop -1 -i "/home/pi/Documents/Youtube/video720p.mp4" -c:v copy -c:a aac -f flv -max_muxing_queue_size 400 rtmp://a.rtmp.youtube.com/live2/pfjd-jhjs-k3td-xxxx

  Or i should buffer it before streaming or re-encode the audio before streaming ?

  Thanks in advance !

• Programming in C : Opening, Reading and Transcoding of Live TV with libavcodec. libavformat etc

  19 décembre 2011, par mmoment

  I'm currently developing a live streaming Software for my University Project.

  I am supposed to open a Live Video Stream from a USB Stick( I am using the Hauppauge WinTV-HVR 950Q under Linux) and read the Stream.
  Then I'm supposed to transcode it to h246. and send it to some devices in the Network.

  My Problem

  ---

  I can use the v4l API to access the USB Stick, but transcoding does currently not work as far as I know, therefore I want to use the libav to do so. I know that using the command line tools transcoding of live streams with ffmpeg is not a big deal, but doing so in C seems to be more of a problem.

  1. Here's how I open some static Video File :

     static char* path = "./video.mpeg" ;
     AVFormatContext *pFormatCtx ;

     av_register_all() ;

     if(av_open_input_file(&pFormatCtx, path, NULL, 0, NULL) !=0)
     
     printf("Opening file \"%s\" failed", path) ;
     return -1 ;
     else printf("Opening the file \"%s\" succeeded", path) ;

  2. Here's how I understand to how open a Live Feed

     static char* path = "/dev/dvb/adapter0/dvr0" ;
     AVFormatContext *pFormatCtx ;

     av_register_all() ;
     avdevice_register_all() ;

     if(avformat_open_input(&pFormatCtx, path, NULL, NULL) != 0)
     
     perror("avformat_open_input") ;
     return -1 ;
     else printf("Yay") ;

  3. Here's how I understand to how open a Live Feed

     if(av_find_stream_info(pFormatCtx)<0)
     
     printf("Could not find any Stream Information the file \"%s\"", path) ;
     return -1 ;
     
     // Dump information about file onto standard error
     dump_format(pFormatCtx, 0, path, 0) ;
     AVCodecContext *pCodecCtx ;

     // Find the first video stream
     int videoStream=-1 ;
     for(i=0 ; inb_streams ; i++)
     

     if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO)
     
     {
     
         videoStream=i;
     
         break;
     
     }

     if(videoStream==-1) return -1 ; // Didn't find a video stream

     // Get a pointer to the codec context for the video stream
     pCodecCtx=pFormatCtx->streams[videoStream]->codec ;

     AVCodec *pCodec ;

     // Find the decoder for the video stream
     pCodec=avcodec_find_decoder(pCodecCtx->codec_id) ;
     if(pCodec==NULL)
     
     fprintf(stderr, "Unsupported codec !\n") ;
     return -1 ; // Codec not found
     
     //Open codec
     if(avcodec_open(pCodecCtx, pCodec)<0)
     
     printf("Could not open the Codec") ;
     return -1 ; // Could not open codec
     

  So now how can you help me ?

  I would really appreciate it if anyone knew how to open a live stream and could give me a good example.

• How to loop through a 10 sec video for a live stream using ffmpeg [duplicate]

  27 avril 2021, par Xternet

  I'm using the below code to live stram to Instagram, now I want to loop a 10sec video so it'll go on forever as long as the process is running, it'll keep streaming. How do I go about it.

  &#xA;

  $videoFilename = "/var/www/html/video.mp4";

$broadcastProcess = $ffmpeg->runAsync(sprintf(
            '-rtbufsize 256M -re -i %s -acodec libmp3lame -ar 44100 -b:a 128k -pix_fmt yuv420p -profile:v baseline -s 720x1280 -bufsize 6000k -vb 400k -maxrate 1500k -deinterlace -vcodec libx264 -preset veryfast -g 30 -r 30 -f flv %s',
            \Winbox\Args::escape($videoFilename),
            \Winbox\Args::escape($streamUploadUrl)
        ));


  &#xA;