Recherche avancée

Sur d’autres sites (4661)

• mp4Parser : How to create a video file with background audio from an mp3 file

  30 mai 2015, par Manu Antony

  I am trying create an android app which merges a video and audio file using mp4Parser. I succeeded when I merge two mp4 file into a single file that displays the video of the first one and plays the audio of the second file.

  But I couldn’t use an mp3 file as the audio source.

  The below code returns exception when I try to create Movie object with an mp3 file. The same code works fine with m4a and mp4 files.

  Movie audio;
  
      try {
  
          String audioFileName    =   Environment.getExternalStorageDirectory().toString()+"/music.mp3";
  
          audio = new MovieCreator().build(audioFileName);
  
      } catch (IOException e) {
  
          e.printStackTrace();
  
          return false;
  
      } catch (NullPointerException e) {
  
          e.printStackTrace();
  
          return false;
  
      }

  Is it possible to create Movie object from an mp3 file ?

  Anyone please help me on this

• WebRTC Multi-Stream recording

  11 janvier 2021, par Tim Specht

  I'm currently trying to build a WebRTC streaming architecture that contains multiple users streaming content from their camera in the same "room" and a SFU / MCU on server-side "recording" the incoming video packets, merging them into one image and re-distributing them to the viewers as either RTMP or HLS for added scalability.

  


  Upon doing some initial research on this, Janus Gateway seems like a good fit for this given it's wide adoption across the space + their (seemingly) extensible plugin architecture. Thus, I'm currently trying to figure out what a recommended architecture for my use-case would look like.
I looked at the following plugins :

  


  

  • Janus Streaming

  


  • Janus Recordings

  


  


  While Janus and the Streaming plugin seem like a good start to get the broadcasting aspect within the group of casters in the room, I'm trying to piece together how I could combine the different video sources into a combined one (split horizontally for example if there are 2 casters active) and retransmit the final result as something optimized for broadcast-consumption like HLS. Some of the ways I could imagine doing that :

  


  

  • Implement a custom Janus plugin that transcodes the incoming buffers on the gateway itself

  


  • Forwarding the incoming packets via RTP to a Transcoding server

    

    • In this specific case I am not sure what would be best to implement that ? Are the video frames different tracks ? Could I stream all of them to the same port and have ffmpeg or something similar take care of the merging for me ?

    


    


  


  


• How can I optimize MP4 file encoding in openRTSP to the same level as FFmpeg ?

  2 juillet 2018, par Wolfgang Klenk

  I currently receive and store a RTSP stream from a camera with openRTSP with a command like this :

  openRTSP -4 "rtsp://192.168.41.185/rtsp_tunnel?h26x=4&line=1&inst=2" > movie.mp4

  I can do the same using FFmpeg :

  ffmpeg -i "rtsp://192.168.41.185/rtsp_tunnel?h26x=4&line=1&inst=2" -vcodec copy movie.mp4

  The video frames from the camera are 1280x720 (H.264) at around 30 fps and have a milliseconds timestamp stamped in. When I view the movie.mp4 created by ffmpeg it looks pretty nice, the seconds stamped into the video stream seem rather accurate. On the contrary, if I view the movie.mp4 created by openRTSP, the seconds in the video timestamp last definitively longer than the ones in reality. So one second on video could last two seconds in reality. I made several tests, and it is not an issue of network performance or of handling the messages received from the camera. The reason seems to be the part where the messages are encoded into this MP4 container.

  Is FFmpeg so much faster doing this than openRTSP ?

  Can I optimize the MP4 encoding in openRTSP somehow ?