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[maxsap]

Hello all, I am writting an android program and as part of it I am using AudioTrack and AudioRecord to stream into memory raw pcm. The problem is that I would like to use RTP (currently using jlibRTP) and the classes mentioned above use 16 bit samples (short) and jlibRTP supports 8 bit (byte) so I thought of using java's ByteBuffer to do all the derty work of the convertion. The problem is that it doesn't work, any suggestions?
This is used for recording:

// Allocate Recorder and Start Recording…

		int bufferRead = 0;

		int bufferSize = AudioRecord.getMinBufferSize(this.getFrequency(), this

				.getChannelConfiguration(), this.getAudioEncoding());

		AudioRecord recordInstance = new AudioRecord(

				MediaRecorder.AudioSource.MIC, this.getFrequency(), this

						.getChannelConfiguration(), this.getAudioEncoding(),

				bufferSize);

		short[] tempBuffer = new short[bufferSize];

		recordInstance.startRecording();

		while (this.isRecording) {

			// Are we paused?

			synchronized (mutex) {

				if (this.isPaused) {

					try {

						mutex.wait(250);

					} catch (InterruptedException e) {

						throw new IllegalStateException("Wait() interrupted!",

								e);

					}

					continue;

				}

			}


			bufferRead = recordInstance.read(tempBuffer, 0, bufferSize);

			if (bufferRead == AudioRecord.ERROR_INVALID_OPERATION) {

				throw new IllegalStateException(

						"read() returned AudioRecord.ERROR_INVALID_OPERATION");

			} else if (bufferRead == AudioRecord.ERROR_BAD_VALUE) {

				throw new IllegalStateException(

						"read() returned AudioRecord.ERROR_BAD_VALUE");

			} else if (bufferRead == AudioRecord.ERROR_INVALID_OPERATION) {

				throw new IllegalStateException(

						"read() returned AudioRecord.ERROR_INVALID_OPERATION");

			}

			try {

				int tempint;

				ByteBuffer bb = ByteBuffer.allocate(tempBuffer.length*2);

				bb.order(ByteOrder.LITTLE_ENDIAN);

				for (int idxBuffer = 0; idxBuffer < bufferRead; ++idxBuffer) {

					bb.putShort(idxBuffer,tempBuffer[idxBuffer]);	

//					Log.e("maxsap","------------* COUNTER -> "+idxBuffer+" BUFFER VALUE IN SHORT -> "+ tempBuffer[idxBuffer]+" BYTEBUFFER VALUE -> "+bb.get(idxBuffer)+"*-----------");

					dataOutputStreamInstance.writeByte(bb.get(idxBuffer));

				}

			} catch (IOException e) {

				Log.e("maxsap",e.getLocalizedMessage());

			}

and this is used for convertion and playback:

int musicLength = (int)(file.length()/2);

		  short[] music = new short[musicLength];



		 // try {

		    // Create a DataInputStream to read the audio data back from the saved file.

		    InputStream is;

			try {

				is = new FileInputStream(file);

			

		    Log.d("maxsap", "------------* GETTING INPUT STREAM*-----------");

		    BufferedInputStream bis = new BufferedInputStream(is);

		    Log.d("maxsap", "------------* GETTING BUFFERED INPUT*-----------");

		    DataInputStream dis = new DataInputStream(bis);

		    Log.d("maxsap", "------------* GETTING DATA INPUT*-----------");

		      

		    // Read the file into the music array.

		    int i = 0;

		    Log.d("maxsap", "------------* READING FROM STREAM*-----------");

		    ByteBuffer bb = ByteBuffer.allocate(music.length*2);

			bb.order(ByteOrder.LITTLE_ENDIAN);	

			while (dis.available() > 0) {

//				Log.d("maxsap", "------------* COUNTER -> "+i+" BUFFER VALUE -> "+dis.readByte()+" *-----------");

				Log.d("maxsap","counter->"+i);

				bb.putShort(dis.readByte());

				i++;

			}

		    Log.d("maxsap", "------------* STREAM READED *-----------");

//		    Integer tempint;

//		    for (int x=1, j=0; x<music.length; x+=2, j++){

//				tempint = ((int) music[x])& 0xFF;

//				music[j] = tempint.shortValue();

//				Log.e("maxsap","------------*"+ music[j]+"*-----------");

//			}


		    // Close the input streams.

		    dis.close();     

		    // Create a new AudioTrack object using the same parameters as the AudioRecord

		    // object used to create the file.

		    AudioTrack audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, 

		    		11025, 

		                                           AudioFormat.CHANNEL_CONFIGURATION_MONO,

		                                           AudioFormat.ENCODING_PCM_16BIT, 

		                                           musicLength, 

		                                           AudioTrack.MODE_STREAM);

		    Log.d("maxsap", "------------* audioTrack initialized *-----------");

		    // Start playback

		    audioTrack.play();

		    for(int x=0; x<music.length; x++){

		    	music[i] = bb.getShort(i);

		    	

		    }

		    // Write the music buffer to the AudioTrack object

		    audioTrack.write(music, 0, musicLength);

//		  } catch (Throwable t) {

//		    Log.e("AudioTrack",t.getLocalizedMessage());

//		  }

			} catch (FileNotFoundException ex) {

				Log.e("maxsap", "------------* FileNotFoundException *-----------");

			} catch (IOException e) {

				Log.e("maxsap", "------------* IOException *-----------");

			} catch(RuntimeException run){

				Log.e("maxsap", "------------* RuntimeException *-----------");

				Log.e("maxsap", "------------* Caused By: "+run.getMessage()+" *-----------");

			}

		}

Note that the arguments for audioTrack and AudioRecord are:
frequency:11025
ChannelConfiguration:AudioFormat.CHANNEL_CONFIGURATION_MONO
audioEncoding : AudioFormat.ENCODING_PCM_16BIT
also there is a known bug in those classes and can't use directly 8 bit configuration.
thanks in advanced maxsap.

Edited by Roger, 23 July 2011 - 02:47 PM.