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• Issue while opening a .mp4 file - CPU shoots up 100%

  16 juillet 2014, par AnilJ

  I am using IMediaWriter, to write out about 20 video frames into an independent .mp4 file and creating a new writer to write a new file. This is a logic (not so efficient one), I’ve used to chunk the web-cam feed into chunks. I am able to successfully able to create multiple .mp4 video files and when opened then in a VLC player, they can be played back.

  However, when I try to open one of the chunked file into a new IContainer object (see below code snippet), my program :

  • Gets stuck at the container.open() call ( see * below), and the CPU
    utilization shoots above 100%.
  • Sometimes it throws an error "moov atom not found", and hence can not open the file.

  In both the cases, my program does not work.

  <code snippet="snippet">
  
          String file = BASE_PATH + File.separator + "output" + File.separator + "output.mp4";  // This is one of the chunk.
  
          IContainer container = IContainer.make();
  
          FileChannel channel = null;
  
  
  
          try {
  
              @SuppressWarnings("resource")
  
              RandomAccessFile inFile = new RandomAccessFile(chunkFile, "r");
  
              channel = inFile.getChannel();
  
          } catch (FileNotFoundException e) {
  
              e.printStackTrace();
  
          }
  
  
  
          // Open up the container
  
  ***        int retval = container.open(channel, IContainer.Type.READ, null);
  
          if (retval &lt; 0) {
  
              // This little trick converts the non friendly integer return value into 
  
              // a slightly more friendly object to get a human-readable error name
  
              IError error = IError.make(retval);
  
              throw new IllegalArgumentException("could not open file: " + mInputFileChannel + "; Error: " + error.getDescription());
  
          }
  
  <code snippet="snippet">
  
  

  Subsequently, I ran the AtomicParsley tool to dump the file content, and it prints following. I am not aware of video file internals and seeking help to know the issue here and potential solution.

  Atom ftyp @ 0 of size: 28, ends @ 28
  
  Atom free @ 28 of size: 8, ends @ 36
  
  Atom mdat @ 36 of size: 45175, ends @ 45211
  
  Atom moov @ 45211 of size: 1052, ends @ 46263
  
       Atom mvhd @ 45219 of size: 108, ends @ 45327
  
       Atom trak @ 45327 of size: 839, ends @ 46166
  
           Atom tkhd @ 45335 of size: 92, ends @ 45427
  
           Atom edts @ 45427 of size: 36, ends @ 45463
  
               Atom elst @ 45435 of size: 28, ends @ 45463
  
           Atom mdia @ 45463 of size: 703, ends @ 46166
  
               Atom mdhd @ 45471 of size: 32, ends @ 45503
  
               Atom hdlr @ 45503 of size: 45, ends @ 45548
  
               Atom minf @ 45548 of size: 618, ends @ 46166
  
                   Atom vmhd @ 45556 of size: 20, ends @ 45576
  
                   Atom dinf @ 45576 of size: 36, ends @ 45612
  
                       Atom dref @ 45584 of size: 28, ends @ 45612
  
                           Atom url  @ 45600 of size: 12, ends @ 45612
  
                   Atom stbl @ 45612 of size: 554, ends @ 46166
  
                       Atom stsd @ 45620 of size: 198, ends @ 45818
  
                           Atom mp4v @ 45636 of size: 182, ends @ 45818
  
                               Atom esds @ 45722 of size: 96, ends @ 45818
  
                       Atom stts @ 45818 of size: 176, ends @ 45994
  
                       Atom stss @ 45994 of size: 24, ends @ 46018
  
                       Atom stsc @ 46018 of size: 28, ends @ 46046
  
                       Atom stsz @ 46046 of size: 100, ends @ 46146
  
                       Atom stco @ 46146 of size: 20, ends @ 46166
  
       Atom udta @ 46166 of size: 97, ends @ 46263
  
           Atom meta @ 46174 of size: 89, ends @ 46263
  
               Atom hdlr @ 46186 of size: 33, ends @ 46219
  
               Atom ilst @ 46219 of size: 44, ends @ 46263
  
                   Atom ©too @ 46227 of size: 36, ends @ 46263
  
                       Atom data @ 46235 of size: 28, ends @ 46263
  
  ------------------------------------------------------
  
  Total size: 46263 bytes; 31 atoms total. AtomicParsley from svn built on Jul 15 2014 (utf8)
  
  Media data: 45175 bytes; 1088 bytes all other atoms (2.352% atom overhead).
  
  Total free atom space: 8 bytes; 0.017% waste.
  
  ------------------------------------------------------

  I am not sure if there is anything wrong with the file itself. Can you please help me understand this ?

• How to live stream an mp4 video in android from server - only works in KitKat ?

  15 octobre 2014, par user3522608

  How to stream an MP4 video in Android from a server ? Here is my code but it only works for KitKat.

   private void play() {
  
              try {
  
                  final String path = ""
  
                  Log.v(TAG, "path: " + path);
  
                  if (path == null || path.length() == 0) {
  
                      Toast.makeText(getApplicationContext(), "File URL/path is empty",
  
                              Toast.LENGTH_LONG).show();
  
  
  
                  } else {
  
                      // If the path has not changed, just start the media player
  
                      if (path.equals(current) && mVideoView != null) {
  
  
  
                          mVideoView.start();
  
                          mVideoView.requestFocus();
  
                          return;
  
                      }
  
                      current = path;
  
                      mVideoView.setVideoPath(getDataSource(path));
  
  
  
                      mVideoView.start();
  
                      mVideoView.requestFocus();
  
  
  
                  }
  
              } catch (Exception e) {
  
                  Log.e(TAG, "error: " + e.getMessage(), e);
  
                  if (mVideoView != null) {
  
                      mVideoView.stopPlayback();
  
                  }
  
              }
  
          }
  
  
  
          private String getDataSource(String path) throws IOException {
  
              if (!URLUtil.isNetworkUrl(path)) {
  
                  return path;
  
              } else {
  
                  URL url = new URL(path);
  
                  URLConnection cn = url.openConnection();
  
                  cn.connect();
  
                  InputStream stream = cn.getInputStream();
  
                  if (stream == null)
  
                      throw new RuntimeException("stream is null");
  
                  File temp = File.createTempFile("mediaplayertmp", "dat");
  
                  temp.deleteOnExit();
  
                  String tempPath = temp.getAbsolutePath();
  
                  FileOutputStream out = new FileOutputStream(temp);
  
                  byte buf[] = new byte[256];
  
                  do {
  
                      int numread = stream.read(buf);
  
                      if (numread <= 0)
  
                          break;
  
                      out.write(buf, 0, numread);
  
                  } while (true);
  
                  try {
  
                      stream.close();
  
                  } catch (IOException ex) {
  
                      Log.e(TAG, "error: " + ex.getMessage(), ex);
  
                  }
  
  
  
                  return tempPath;
  
              }
  
          }         

• MOOV atom is not being written to the output.

  18 juillet 2014, par AnilJ

  I am facing a problem where a MOOV atom is not written to the end of the file, and the file is not playable by the vlc player. Also, FFmpeg command gives me the following error.

  [mov,mp4,m4a,3gp,3g2,mj2 @ 0x2334ba0] moov atom not found
  
  queueout/1000_wrecord.mp4: Invalid data found when processing input

  In my design, I am using an object of DataChunkQueue class to initialize the IContainer object, where it writes into this queue when it calls IContainer.WritePacket(packet) method. Finally when the recording is complete, I am flushing out this queue into a file. However, when I try to play the file, above error is thrown. When I test with the FLV file type however, I am able to playout the file correctly.

  I am not sure what is the issue with the MP4 file and why it does not write the MOOV item to the end. Can anyone offer me an suggestions as to how this can be resolved ?

  I am pasting below some of the code snippets for reference.

  public class DataChunkQueue implements ByteChannel {
  
  
  
      private ConcurrentLinkedQueue<datachunk> mChunkQueue = null;
  
      private static String BASE_PATH = null;
  
      private static String mOutputFileName = null;
  
      private FileChannel mOutputFileChannel = null;
  
  
  
      // constructor
  
      public DataChunkQueue() {
  
          mChunkQueue = new ConcurrentLinkedQueue<datachunk>();
  
      }
  
  
  
      @Override
  
      public void close() throws IOException {
  
          return;
  
      }
  
  
  
      @Override
  
      public boolean isOpen() {
  
          return true;
  
      }
  
  
  
      @Override
  
      public int write(ByteBuffer buffer) throws IOException {
  
          DataChunk vChunk = new DataChunk(buffer);
  
          mChunkQueue.add(vChunk);    
  
          return 0;
  
      }
  
  
  
      public int read(ByteBuffer buffer) throws IOException {
  
  
  
          int result = 0;
  
  
  
          buffer = mChunkQueue.poll().GetBuffer();
  
          if (buffer != null ) {
  
              result = 0;
  
          } else {
  
              result = 1;
  
          }
  
  
  
          return result;
  
      }
  
  }
  
  
  
  private boolean InitStreamEncoder() {
  
  
  
      DataChunkQueue mOutQueue = null;
  
      // Change this to change the frame rate you record at
  
      mFrameRate = IRational.make(Constants.FRAME_RATE, 1);
  
  
  
      // try opening a container format
  
      mOutFormat = IContainerFormat.make();
  
      mOutFormat.setOutputFormat(mRecordFormat, null, null);
  
  
  
      // Initialize the output container. 
  
      mOutputContainer = IContainer.make();
  
      int retval = mOutputContainer.open(mOutQueue, IContainer.Type.WRITE, mOutFormat);
  
      if (retval &lt; 0)
  
          throw new RuntimeException("could not open data output stream buffer");
  
  
  
      // Guess the Encoding CODEC based on the type of input file.
  
      ICodec videoCodec = ICodec.guessEncodingCodec(null, null, ("out." + mRecordFormat), null, ICodec.Type.CODEC_TYPE_VIDEO);
  
      if (videoCodec == null)
  
          throw new RuntimeException("could not guess a codec");
  
  
  
      // Initialize the encoding parameters.
  
      mOutStream = mOutputContainer.addNewStream(videoCodec);
  
      mOutStreamCoder = mOutStream.getStreamCoder();
  
  
  
      mOutStreamCoder.setNumPicturesInGroupOfPictures(Constants.GOP);
  
      mOutStreamCoder.setCodec(videoCodec);
  
  
  
      //mOutStreamCoder.setBitRate(Constants.BITRATE);
  
      //mOutStreamCoder.setBitRateTolerance(Constants.TOLERANCE);
  
      mOutStreamCoder.setPixelType(IPixelFormat.Type.YUV420P);
  
      mOutStreamCoder.setWidth(Constants.MAIN_SCREEN_WIDTH);
  
      mOutStreamCoder.setHeight(Constants.MAIN_SCREEN_HEIGHT);
  
      //mOutStreamCoder.setFlag(IStreamCoder.Flags.FLAG_QSCALE, true);
  
      //mOutStreamCoder.setGlobalQuality(0);
  
  
  
      mOutStreamCoder.setFrameRate(mFrameRate);
  
      mOutStreamCoder.setTimeBase(IRational.make(mFrameRate.getDenominator(), mFrameRate.getNumerator()));
  
  
  
      retval = mOutStreamCoder.open(null, null);
  
      if (retval &lt; 0) {
  
          System.out.println("could not open input decoder");
  
          return false;       
  
      }
  
  
  
      retval = mOutputContainer.writeHeader();
  
      if (retval &lt; 0) {
  
          System.out.println("could not write file header");
  
          return false;
  
      }
  
  
  
      return true;
  
  }
  
  </datachunk></datachunk>

  This function is called at the very end to write the trailer.

  public void Cleanup() {
  
      if (mOutputContainer != null) {
  
          mOutputContainer.flushPackets();
  
          mOutputContainer.writeTrailer();
  
          mOutputContainer.close();
  
      }
  
  
  
      if (mOutStreamCoder != null) {
  
          mOutStreamCoder.close();
  
          mOutStreamCoder = null;
  
      }
  
  }