/*******************************************************************************
* SDR Trunk
* Copyright (C) 2014 Dennis Sheirer
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>
******************************************************************************/
package record.wave;
import javax.sound.sampled.AudioFormat;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
public class WaveUtils
{
public static final byte[] RIFF_CHUNK = {(byte)0x52, (byte)0x49, (byte)0x46, (byte)0x46}; //RIFF
public static final byte[] WAV_FORMAT = {(byte)0x57, (byte)0x41, (byte)0x56, (byte)0x45}; //WAVE
public static final byte[] CHUNK_FORMAT = {(byte)0x66, (byte)0x6D, (byte)0x74, (byte)0x20}; //fmt space
public static final byte[] CHUNK_DATA = {(byte)0x64, (byte)0x61, (byte)0x74, (byte)0x61}; //data
public static final int PCM_FORMAT = 1;
/**
* Creates a wave file header with the RIFF chunk descriptor and the WAVE
* format chunk 1 and chunk 2 header
*/
public static ByteBuffer getWaveHeader( AudioFormat format )
{
ByteBuffer descriptor = ByteBuffer.allocate( 44 );
descriptor.order( ByteOrder.LITTLE_ENDIAN );
/* Chunk ID = RIFF */
descriptor.put( (byte)0x52 ); //R
descriptor.put( (byte)0x49 ); //I
descriptor.put( (byte)0x46 ); //F
descriptor.put( (byte)0x46 ); //F
/* Chunk Size = 36 bytes (initial empty size) */
descriptor.put( (byte)36 );
descriptor.put( (byte)0 );
descriptor.put( (byte)0 );
descriptor.put( (byte)0 );
/* Format = WAVE */
descriptor.put( (byte)0x57 ); //W
descriptor.put( (byte)0x41 ); //A
descriptor.put( (byte)0x56 ); //V
descriptor.put( (byte)0x45 ); //E
/* Sub Chunk 1 ID */
descriptor.put( (byte)0x66 ); //f
descriptor.put( (byte)0x6D ); //m
descriptor.put( (byte)0x74 ); //t
descriptor.put( (byte)0x20 ); //space
/* SubChunk1Size = 1 */
descriptor.put( (byte)0x10 );
descriptor.put( (byte)0x0 );
descriptor.put( (byte)0x0 );
descriptor.put( (byte)0x0 );
/* Audio format = 1 (Uncompressed PCM) */
descriptor.put( (byte)0x1 );
descriptor.put( (byte)0x0 );
/* Number of Channels */
descriptor.asShortBuffer().put( (short)format.getChannels() );
descriptor.position( descriptor.position() + 2 );
/* Sample Rate - assumes integral sample rate */
descriptor.asIntBuffer().put( (int)format.getSampleRate() );
descriptor.position( descriptor.position() + 4 );
int frameByteRate = format.getChannels() * format.getSampleSizeInBits() / 8;
/* Byte Rate = sample rate * channels * bits per sample / 8 */
int byteRate = (int)( format.getSampleRate() * frameByteRate );
descriptor.asIntBuffer().put( byteRate );
descriptor.position( descriptor.position() + 4 );
/* Block Align */
descriptor.asShortBuffer().put( (short)frameByteRate );
descriptor.position( descriptor.position() + 2 );
/* Bits per Sample */
descriptor.asShortBuffer().put( (short)( format.getSampleSizeInBits() ) );
descriptor.position( descriptor.position() + 2 );
/* Sub Chunk 2 ID */
descriptor.put( (byte)0x64 ); //d
descriptor.put( (byte)0x61 ); //a
descriptor.put( (byte)0x74 ); //t
descriptor.put( (byte)0x61 ); //a
/* Sub Chunk 2 Size */
descriptor.put( (byte)0x0 );
descriptor.put( (byte)0x0 );
descriptor.put( (byte)0x0 );
descriptor.put( (byte)0x0 );
return descriptor;
}
}