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• Xuggler decode H264 packets

  18 novembre 2015, par Roy Bean

  I’m making a test with xuggler, and I’m observing a behavior that I don’t understand.

  So I have a H264 frame, stored in a file and I want to decode it.
  Bassically I need of the IVideoPicture to then get a buffred image.

  for the same same packet I need of 10 tries until it retrieved that the IVideoPicture is complete.

  this is what ffmpeg does when reads the frame :

  Input #0, h264, from 'sample1.jpg':
  
  Duration: N/A, bitrate: N/A
  
  Stream #0:0: Video: h264 (Baseline), yuv420p, 352x288, 25 tbr, 1200k tbn, 50 tbc

  Can someone of xuggler or ffmpeg knowledge explain what is happen ?

  My code bellow :

  IContainer container = IContainer.make();
  
  
  
  RandomAccessFile aFile = new RandomAccessFile("c://sample1Frame/sample1.jpg","r");
  
  IContainerFormat format = IContainerFormat.make();
  
  format.setInputFormat("h264");
  
  container.open(aFile, IContainer.Type.READ, null);
  
  int numStreams = container.getNumStreams();
  
  
  
  
  
  IStreamCoder videoCoder = null;
  
  for(int i = 0; i < numStreams; i++)
  
  {
  
      IStream stream = container.getStream(i);
  
      // Get the pre-configured decoder that can decode this stream;
  
      IStreamCoder coder = stream.getStreamCoder();
  
      if(coder.getCodecType() == ICodec.Type.CODEC_TYPE_VIDEO)
  
      {
  
          System.out.println("coder"); 
  
      }
  
      videoCoder = coder;
  
  }
  
  
  
  // The timebase here is used as the camera frame rate    
  
  videoCoder.setTimeBase(IRational.make(25,1));
  
  
  
  // we need to tell the driver what video with and height to use
  
  videoCoder.setWidth(352);
  
  videoCoder.setHeight(288);
  
  
  
  if(videoCoder.open(null , null) < 0){
  
      System.err.println("Could not open video decoder for input container");
  
      return;
  
  }
  
  //      videoCoder.setFlag(IStreamCoder.Flags.FLAG_QSCALE,true);
  
  //      videoCoder.setFlag(IStreamCoder.Flags.FLAG2_FAST,true);
  
  
  
  IPacket packet = IPacket.make();
  
  //      long firstTimestampInStream = Global.NO_PTS;
  
  //      long systemClockStartTime = 0;
  
  int complete = 1;
  
  
  
  
  
  while(container.readNextPacket(packet) >= 0){
  
      int trys= 1;
  
      System.out.println("PCK = ");
  
      while(true)
  
      {
  
          trys++;
  
          System.out.println("trys = " + trys);
  
          System.out.println("packet " + packet.getSize());
  
          IVideoPicture picture = IVideoPicture.make(videoCoder.getPixelType(), videoCoder.getWidth(), videoCoder.getHeight());
  
  
  
  
  
          //TODO
  
          int offset = 0;
  
          while(offset < packet.getSize())
  
          {
  
              /*
  
               * Now, we decode the video, checking for any errors.
  
               * 
  
               */
  
              System.out.println("packet getTimeBase " + packet.getTimeBase());
  
              System.out.println("vc getTimeBase " + videoCoder.getTimeBase());
  
              System.out.println("vc getCodecID " + videoCoder.getCodecID().toString());
  
              int bytOffset = videoCoder.decodeVideo(picture, packet, offset);
  
              Logger.getLogger(VideoSamsung.class.getName()).log(Level.SEVERE,"bytOffset =  " + bytOffset);
  
  
  
              if(bytOffset < 0){
  
                  //                  videoCoder.close();
  
                  //                  //                  picture.setComplete(true, com.xuggle.xuggler.IPixelFormat.Type.YUV420P, 352, 288, packet.getPts());
  
                  //                  System.err.println("picture.isComplete()"+picture.isComplete());
  
                  //                                      BufferedImage sdf = Utils.videoPictureToImage(picture);
  
                  //                                      File outputfile = new File("c://sdf/image.jpg");
  
                  //                                      ImageIO.write(sdf, "jpg", outputfile);
  
                  Logger.getLogger(VideoSamsung.class.getName()).log(Level.SEVERE,"BUMMMMMM!!!!!!!!!!!!!!!!!!!");
  
                  break;
  
              }else{
  
                  //System.out.println(DatatypeConverter.printBase64Binary(videoCoder.getExtraData().getByteArray(0, videoCoder.getExtraData().getSize())));
  
              }
  
              offset += bytOffset;
  
              System.err.println("picture.isComplete()"+picture.isComplete());
  
  
  
              /*
  
               * Some decoders will consume data in a packet, but will not be able to construct
  
               * a full video picture yet.  Therefore you should always check if you
  
               * got a complete picture from the decoder
  
               */
  
  
  
          }//end while(offset < packet.getSize())
  
  
  
          if (picture.isComplete())
  
          {
  
              System.out.println("isComplete");
  
              IVideoPicture newPic = picture;
  
              BufferedImage sdf = Utils.videoPictureToImage(picture);
  
              File outputfile = new File("c://sdf/image_"+complete+".jpg");
  
              ImageIO.write(sdf, "jpg", outputfile);
  
              complete++;
  
              System.out.println("trys = " + trys);
  
              break;
  
              //              System.exit(0);
  
          }else{
  
              System.out.println("Picture is not Complete");
  
          }
  
  
  
          if(trys > 20){
  
              System.out.println("FAIL!!!!!!!!!!  trys = " + trys);
  
              break;
  
          }
  
      }
  
  }
  
  /*
  
   * Technically since we're exiting anyway, these will be cleaned up by 
  
   * the garbage collector... but because we're nice people and want
  
   * to be invited places for Christmas, we're going to show how to clean up.
  
   */
  
  if (videoCoder != null)
  
  {
  
      videoCoder.close();
  
      videoCoder = null;
  
  }
  
  if (container !=null)
  
  {
  
      container.close();
  
      container = null;
  
  }

  the console output :

      PCK = 
  
  trys = 2
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  Picture is not Complete
  
  trys = 3
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  picture.isComplete()false
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  Picture is not Complete
  
  picture.isComplete()false
  
  trys = 4
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  picture.isComplete()false
  
  Picture is not Complete
  
  trys = 5
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  picture.isComplete()false
  
  Picture is not Complete
  
  trys = 6
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  picture.isComplete()false
  
  Picture is not Complete
  
  trys = 7
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  picture.isComplete()false
  
  Picture is not Complete
  
  trys = 8
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  picture.isComplete()false
  
  Picture is not Complete
  
  trys = 9
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  picture.isComplete()false
  
  Picture is not Complete
  
  trys = 10
  
  packet 1748
  
  packet getTimeBase 1/1200000
  
  vc getTimeBase 25/1
  
  vc getCodecID CODEC_ID_H264
  
  Nov 18, 2015 5:39:11 PM filepath main
  
  SEVERE: bytOffset =  1748
  
  picture.isComplete()true
  
  isComplete
  
  trys = 10

• Evolution #3962 (Nouveau) : Générer des JPEG progressifs

  18 juin 2017, par Michel Bystranowski

  Le format JPEG propose un encodage « progressif » qui permet aux navigateurs d’afficher une version peu détaillée de l’image avant la réception complète, ce qui améliore l’expérience utilisateur sur des mauvaises connections. En cherchant un peu je ne trouve pas de contre-indications. Les vieux IE ne supportent pas ce format, mais affichent quand même les images après réception complète, donc pas de changement par rapport aux JPEG « classiques ».

  La librairie GD permet de générer ce genre de JPEG très facilement, il suffit d’appeler la fonction imageinterlace (https://secure.php.net/manual/en/function.imageinterlace.php) avant de générer le JPEG.

  Du coup il me semble qu’on pourrait utiliser ça dans SPIP, en ajoutant simplement un petit imageinterlace($img, 1); dans la fonction _image_imagejpg qui se trouve dans ecrire/inc/filtres_images_mini.php.

• Anomalie #2580 : les icones de l’espace privé sont pas belles et trop petites

  24 mars 2012, par cedric -

  le boussole vraiment atroce est remplacée par r19145 on peut dire que le ticket est plus bloquant, l’ideal étant evidemment d’avoir une proposition complete d’icone ?