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• Play MPEG-2 TS using MseStreamSource

  27 novembre 2022, par Nicolas Séveno

  I need to display a live video stream in a UWP application.

  



  The video stream comes from a GoPro. It is transported by UDP messages. It is a MPEG-2 TS stream. I can play it successfully using FFPlay with the following command line :

  



  ffplay -fflags nobuffer -f:v mpegts udp://:8554


  



  I would like to play it with MediaPlayerElement without using a third party library.

  



  According to the following page :
https://learn.microsoft.com/en-us/windows/uwp/audio-video-camera/supported-codecs
UWP should be able to play it. (I installed the "Microsoft DVD" application in the Windows Store).

  



  I receive the MPEG-2 TS stream with a UdpClient. It works well.
I receive in each UdpReceiveResult a 12 bytes header, followed by 4, 5, 6, or 7 MPEGTS packets (each packet is 188 bytes, beginning with 0x47).

  



  I created a MseStreamSource :

  



  _mseStreamSource = new MseStreamSource();
_mseStreamSource.Opened += (_, __) =>
{
    _mseSourceBuffer = _mseStreamSource.AddSourceBuffer("video/mp2t");
    _mseSourceBuffer.Mode = MseAppendMode.Sequence;
};
_mediaPlayerElement.MediaSource = MediaSource.CreateFromMseStreamSource(_mseStreamSource);


  



  This is how I send the messages to the MseStreamSource :

  



      UdpReceiveResult receiveResult = await _udpClient.ReceiveAsync();
    byte[] bytes = receiveResult.Buffer;
    mseSourceBuffer.AppendBuffer(bytes.AsBuffer());


  



  The MediaPlayerElement displays the message "video not supported or incorrect file name". (not sure of the message, my Windows is in French).

  



  Is it a good idea to use the MseAppendMode.Sequence mode ?
What should I pass to the AppendBuffer method ? The raw udp message including the 12 bytes header or each MPEGTS 188 bytes packet ?

  


• extracting single frame from MediaElemet or FFmpegInterop

  13 janvier 2016, par Jakub Wisniewski

  I am writing app (Windows Phone 8.1 Store App) that allows user to connect to IP Camera. I am using FFmpeg Interop library for ffmpeg which allows me to play eg. rtsp streams in media element. I need now a way to somehow extract a single frame from stream or from media element.

  I have tested other application wchih allows connecting to IP cameras - IP Centcom, and they have working snapshots only for mjpeg streams as far as I now (they were not working for rtsp). Becouse of that I belive that it is impossible or at very least very hard to export frame from media element.

  I have different question - if anyone has ever used FFmpeg Interop and would like to help/explain me how could I modify/extend FFmpegInteropMSS to add method called ’GetThumbnailForStream’ that would work similary to ’GetMediaStreamSource’ but would return single frame (bitmap or jpg) instead of MediaStreamSource ?

  Every help would be appreciated

  EDIT :

  I have found something ;

  in MediaSampleProvider in method WriteAVPacketToStream (line 123) there is line

  auto aBuffer = ref new Platform::Array(avPacket->data, avPacket->size);

  and I belive that this is the place that stores single frame data that is needed to convert into bitmap - now since I do not know c++ too much I have a question : how can I convert it into a form that I could return via public method ?

  When returning :

  Platform::Array^

  I get

  ’FFmpegInterop::MediaSampleProvider’ : a non-value type cannot have any public data members

  EDIT2 :

  Ok I am doing approprate projection to byte according to this microsoft information, now I need to check if this is correct data.

• How to implement a command line of ffmpeg with ffmpeg static lib ?

  19 novembre 2014, par JackPearse

  I need a simple ffmpeg conversion task to be done inside an application :

  ffmpeg -i input_file.m4v -vcodec copy -acodec copy -vbsf h264_mp4toannexb output_file.ts

  This works well using the terminal. I’ve successfully compiled ffmpeg’s static lib. Some examples work perfectly, that means the lib is working. How do I implement the behaviour of the above command line with this library ?

  I looked into ffmpeg.c. But there is so much code inside that it took me hours to get an idea on how it works. Finally I still don’t really understand the whole structure.

  I would be very happy if someone could help me understanding how to use the library to do the very same what the example command line does. (At the end I just want to transmux mp4 files to ts files without reencoding)

  Thanks in advance

  Jack