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• JavaFX MediaPlayer unable to play local m3u8 file

  22 février 2020, par Lennart

  I want to show a live stream of a web cam in my JavaFX application using the MediaPlayer/MediaView. My attempt was to use ffmpeg to record a HLS and to play the resulting m3u8 file, but that throws the following exception (VLC plays the video without problems) :

  MediaException: UNKNOWN : com.sun.media.jfxmedia.MediaException: Could not create player! : com.sun.media.jfxmedia.MediaException: Could not create player!
  
      at javafx.scene.media.MediaException.exceptionToMediaException(MediaException.java:146)
  
      at javafx.scene.media.MediaPlayer.init(MediaPlayer.java:511)
  
      at javafx.scene.media.MediaPlayer.<init>(MediaPlayer.java:414)
  
      at de.fraunhofer.iosb.ias.flow.assessment.management.monitor.MonitorViewController.testStream(MonitorViewController.java:203)
  
      ... 58 more
  
  Caused by: com.sun.media.jfxmedia.MediaException: Could not create player!
  
      at com.sun.media.jfxmediaimpl.NativeMediaManager.getPlayer(NativeMediaManager.java:274)
  
      at com.sun.media.jfxmedia.MediaManager.getPlayer(MediaManager.java:118)
  
      at javafx.scene.media.MediaPlayer.init(MediaPlayer.java:467)
  
      ... 60 more
  
  </init>

  I debugged the player creation and the error occurs inside the constructor of GSTMediaPlayer when GSTMediaPlayer.gstInitPlayer() is called. This native method returns the error code 257, which javafx maps to MediaError.ERROR_MEDIA_NULL.

  I used the following ffmpeg command to record the video :

  ffmpeg -hide_banner -y -rtbufsize 250MB -f dshow -pixel_format yuv420p -video_size 960x720 -i video="Logitech HD Pro Webcam C920" -c:v libx264 -crf 20 -pix_fmt yuv420p out.m3u8

  I’m pretty sure that the encoding matches the requirements of javafx, because if I change the output container from m3u8 to mp4, the video is played without problems using the exact same ffmpeg command.

  This is the output of ffprobe for the m3u8 file :

  Input #0, hls,applehttp, from 'out.m3u8':
  
    Duration: 00:00:24.23, start: 1.466667, bitrate: 0 kb/s
  
    Program 0
  
      Metadata:
  
        variant_bitrate : 0
  
      Stream #0:0: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p, 960x720, 30 fps, 30 tbr, 90k tbn, 60 tbc

  And for the mp4 file :

  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'out.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf57.41.100
  
    Duration: 00:01:04.93, start: 0.000000, bitrate: 1676 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 960x720, 1673 kb/s, 30 fps, 30 tbr, 10000k tbn, 60 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler

  The resulting m3u8 file looks like this :

  #EXTM3U
  
  #EXT-X-VERSION:3
  
  #EXT-X-TARGETDURATION:9
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXTINF:8.333322,
  
  out0.ts
  
  #EXTINF:8.333333,
  
  out1.ts
  
  #EXTINF:7.133322,
  
  out2.ts
  
  #EXTINF:0.433333,
  
  out3.ts
  
  #EXT-X-ENDLIST

  Update : After I found this reference m3u file, I think that the problem is that the file is stored locally and isn’t delivered via HTTP. The video plays fine with this :

  Media media = new Media("http://download.oracle.com/otndocs/products/javafx/JavaRap/prog_index.m3u8");
  
  MediaPlayer player = new MediaPlayer(media);
  
  player.setAutoPlay(true);
  
  mediaView.setMediaPlayer(player);

  But after I downloaded the reference m3u and all of its segments and tried to open the local file like this, the error occurred again :

  File video = new File("H://Projects//Tools//ref//prog_index.m3u8");
  
  Media media = new Media(video.toURI().toString());
  
  MediaPlayer player = new MediaPlayer(media);
  
  player.setAutoPlay(true);
  
  mediaView.setMediaPlayer(player);

  I tried to change my m3u file so that the segements are referenced with absolute paths. I tried different notations (H:\f\out0.ts, H:/f/out0.ts, H://f//out0.ts, file:/H:/f/out0.ts, file:///H:/f/out0.ts), but I couldn’t get it to work.

• How to modify music pitch in audio of video file and still sound natural

  9 janvier 2020, par Keith Bennett

  I have some karaoke .mp4 video files (legally obtained) for Thai songs, and want to convert the pitch downward to fit my singing range. I’ve gotten most of the way there thanks to https://superuser.com/questions/292833/how-to-change-audio-frequency/1076762#1076762
  using a command line like this :

  ffmpeg -i in.mp4 -af 'asetrate=35280.0,atempo=1.25' out.mp4

  ...but the instruments and human singing voices don’t sound natural at the modified pitch.

  Is there a better way to change the pitch ? I know some commercial products can do this.

  By the way, I wrote a Ruby script to simplify this ffmpeg call ; it’s at https://gist.github.com/keithrbennett/9ba7043792bfb2fcc92d615076a8413f. It enables you to specify a single factor, and modifies both pitch and tempo accordingly.

• How to modify pitch in audio of video file with singing voices

  9 janvier 2020, par Keith Bennett

  I have some karaoke .mp4 video files (legally obtained) for Thai songs, and want to convert the pitch downward to fit my singing range. I’ve gotten most of the way there thanks to https://superuser.com/questions/292833/how-to-change-audio-frequency/1076762#1076762
  using a command line like this :

  ffmpeg -i in.mp4 -af 'asetrate=35280.0,atempo=1.25' out.mp4

  ...but the human singing voices don’t sound natural at the modified pitch.

  Is there a better way to change the pitch ? I know some commercial products can do this.

  By the way, I wrote a Ruby script to simplify this ffmpeg call ; it’s at https://gist.github.com/keithrbennett/9ba7043792bfb2fcc92d615076a8413f. It enables you to specify a single factor, and modifies both pitch and tempo accordingly.