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• avcodec/videotoolbox : extract videotoolbox_{start,stop} helpers

  26 septembre 2017, par Aman Gupta

  avcodec/videotoolbox : extract videotoolbox_start,stop helpers
  These helpers will be used in later commits to automatically restart
  
  the decoder session when SPS changes are encountered.
  Signed-off-by : Aman Gupta <aman@tmm1.net>
  

  • [DH] libavcodec/videotoolbox.c

• Stop JavaCV playback warning

  18 janvier 2018, par Chaoslab

  Problem :
  Receiving a stream of command line warnings as video plays - deprecated pixel format used, make sure you did set range correctly

  Question :
  How can I stop the warnings from happening or being displayed ?

  Update - Fixed :
  The solution was too override the logging callback and don’t do anything in the logging call method. FFmpeg logging is then disabled.

  The reason for the message from FFmpeg is because it is grabbing frames from an old video format so is unavoidable if playing older videos.

  NOTE :
  This solution completely disables all output from FFmpeg. Even FFmpeg errors are muted.

  Code below (just frame grabbing, not timed playback).

  package test.javacv;
  
  
  
  import java.io.File;
  
  
  
  import org.bytedeco.javacv.CanvasFrame;
  
  import org.bytedeco.javacv.FFmpegFrameGrabber;
  
  import org.bytedeco.javacv.Frame;
  
  
  
  import org.bytedeco.javacv.CustomLogCallback;
  
  
  
  public class TestPlay implements Runnable {
  
   private static String      video_loc = null;
  
   private static CanvasFrame canvas    = new CanvasFrame("Test JavaCV player");
  
  
  
   public static void main(String[] args) { new Thread(new TestPlay(args[0])).start(); }
  
  
  
   static {
  
    CustomLogCallback.set();
  
   }
  
  
  
   public void run() { play_video(video_loc); }
  
  
  
   public TestPlay(String loc) {
  
    video_loc = loc;
  
    canvas.setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE);
  
   }
  
  
  
   public static final void play_video(String vid_loc) {
  
    try {
  
     File               file      = new File(vid_loc);
  
     FFmpegFrameGrabber ffmpeg_fg = new FFmpegFrameGrabber(file.getAbsolutePath());
  
     Frame              frm;
  
     ffmpeg_fg.setAudioChannels(0);
  
     ffmpeg_fg.start();
  
     for(;;)
  
      if((frm = ffmpeg_fg.grab()) != null) canvas.showImage(frm);
  
      else {
  
       ffmpeg_fg.setTimestamp(0);
  
       break;
  
      }
  
     ffmpeg_fg.stop();
  
    } catch(Exception ex) { ex("play_video vid_loc:" + vid_loc, ex); }
  
   }
  
  
  
   public static final void ex(String txt, Exception ex)   {
  
    System.out.println("EXCEPTION: " + txt + " stack..."); ex.printStackTrace(System.out); }
  
  }

  Logging class

  // custom logger to override all logging output
  
  package org.bytedeco.javacv;
  
  
  
  import org.bytedeco.javacpp.BytePointer;
  
  
  
  import static org.bytedeco.javacpp.avutil.LogCallback;
  
  import static org.bytedeco.javacpp.avutil.setLogCallback;
  
  
  
  public class CustomLogCallback extends LogCallback {
  
  
  
   static final CustomLogCallback instance = new CustomLogCallback();
  
  
  
   public static CustomLogCallback getInstance() { return instance; }
  
  
  
   public static void set() { setLogCallback(getInstance()); }
  
  
  
   @Override
  
   public void call(int level, BytePointer msg) {}
  
  }

• Stop JavaVC playback warning

  5 novembre 2017, par Chaoslab

  Receiving a stream of command line warnings as video plays - deprecated pixel format used, make sure you did set range correctly

  Question :
  How can I stop the warnings from happening or being displayed ?

  Example code below (just frame grabbing, not timed playback).

  import java.io.File;
  
  
  
  import org.bytedeco.javacv.CanvasFrame;
  
  import org.bytedeco.javacv.FFmpegFrameGrabber;
  
  import org.bytedeco.javacv.Frame;
  
  
  
  public class TestPlay implements Runnable {
  
   private static String      video_loc = null;
  
   private static CanvasFrame canvas    = new CanvasFrame("Test JavaCV player");
  
  
  
   public static void main(String[] args) { new Thread(new TestPlay(args[0])).start(); }
  
  
  
   public void run() { play_video(video_loc); }
  
  
  
   public TestPlay(String loc) { video_loc = loc; }
  
  
  
   public static final void play_video(String vid_loc) {
  
    try {
  
     File               file      = new File(vid_loc);
  
     FFmpegFrameGrabber ffmpeg_fg = new FFmpegFrameGrabber(file.getAbsolutePath());
  
     Frame              frm;
  
     ffmpeg_fg.setAudioChannels(0);
  
     ffmpeg_fg.start();
  
     for(;;)
  
      if((frm = ffmpeg_fg.grab()) != null) canvas.showImage(frm);
  
      else {
  
       ffmpeg_fg.setTimestamp(0);
  
       break;
  
      }
  
     ffmpeg_fg.stop();
  
    } catch(Exception ex) { ex("play_video vid_loc:" + vid_loc, ex); }
  
   }
  
  
  
   public static final void ex(String txt, Exception ex)   {
  
    System.out.println("EXCEPTION: " + txt + " stack..."); ex.printStackTrace(System.out); }
  
  }

  Looking into these possible solutions...

  • Set the correct pixel format before decoding.
  • Turning off FFMpeg warning logging.

  Will update with a fix when found.