Java tutorial
/******************************************************************************* * sdrtrunk * Copyright (C) 2014-2016 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 io.github.dsheirer.record.wave; import io.github.dsheirer.sample.ConversionUtils; import io.github.dsheirer.sample.Listener; import io.github.dsheirer.sample.real.RealBuffer; import org.apache.commons.lang3.Validate; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.IOException; import java.io.InputStream; import java.nio.ByteBuffer; import java.nio.ByteOrder; import java.nio.ShortBuffer; import java.nio.file.Files; import java.nio.file.Path; import java.nio.file.Paths; import java.nio.file.StandardOpenOption; import java.util.Arrays; import java.util.regex.Pattern; public class MonoWaveReader implements AutoCloseable { private final static Logger mLog = LoggerFactory.getLogger(MonoWaveReader.class); private static final Pattern FILENAME_PATTERN = Pattern.compile("(.*_)(\\d+)(\\.wav)"); private Path mPath; private boolean mRealTime; private InputStream mInputStream; private int mDataByteSize = 0; private Listener<RealBuffer> mListener; private byte[] mDataBuffer = new byte[8000]; /** * Wave file reader for PCM 8kHz, 16-bit little-endian format. * * @param path of the wave file * @param realTime to force replay to real-time. Note: you should run this reader on a separate thread if you * choose real time since this reader will sleep the calling thread as needed to effect real-time playback. */ public MonoWaveReader(Path path, boolean realTime) throws IOException { Validate.isTrue(path != null); mPath = path; mRealTime = realTime; open(); } /** * Opens the file */ private void open() throws IOException { if (!Files.exists(mPath)) { throw new IOException("File not found"); } mInputStream = Files.newInputStream(mPath, StandardOpenOption.READ); //Check for RIFF header byte[] buffer = new byte[4]; mInputStream.read(buffer); if (!Arrays.equals(buffer, WaveUtils.RIFF_CHUNK)) { throw new IOException("File is not .wav format - missing RIFF chunk"); } //Get file size mInputStream.read(buffer); int fileSize = ByteBuffer.wrap(buffer).order(ByteOrder.LITTLE_ENDIAN).asIntBuffer().get(); //Check for WAVE format mInputStream.read(buffer); if (!Arrays.equals(buffer, WaveUtils.WAV_FORMAT)) { throw new IOException("File is not .wav format - missing WAVE format"); } //Check for format chunk mInputStream.read(buffer); if (!Arrays.equals(buffer, WaveUtils.CHUNK_FORMAT)) { throw new IOException("File is not .wav format - missing format chunk"); } //Get chunk size mInputStream.read(buffer); int chunkSize = ByteBuffer.wrap(buffer).order(ByteOrder.LITTLE_ENDIAN).asIntBuffer().get(); //Get format mInputStream.read(buffer); ShortBuffer shortBuffer = ByteBuffer.wrap(buffer).order(ByteOrder.LITTLE_ENDIAN).asShortBuffer(); short format = shortBuffer.get(); if (format != WaveUtils.PCM_FORMAT) { throw new IOException("File format not supported - expecting PCM format"); } //Get number of channels short channels = shortBuffer.get(); if (channels != 1) { throw new IOException("Unsupported channel count - mono audio only"); } //Get samples per second mInputStream.read(buffer); int sampleRate = ByteBuffer.wrap(buffer).order(ByteOrder.LITTLE_ENDIAN).asIntBuffer().get(); //Get bytes per second mInputStream.read(buffer); int bytesPerSecond = ByteBuffer.wrap(buffer).order(ByteOrder.LITTLE_ENDIAN).asIntBuffer().get(); mInputStream.read(buffer); //Get frame size shortBuffer = ByteBuffer.wrap(buffer).order(ByteOrder.LITTLE_ENDIAN).asShortBuffer(); short frameSize = shortBuffer.get(); if (frameSize != 2) { throw new IOException("PCM frame size not supported - expecting 2 bytes per frame"); } //Get bits per sample short bitsPerSample = shortBuffer.get(); if (bitsPerSample != 16) { throw new IOException("PCM sample size not supported - expecting 16 bits per sample"); } mInputStream.read(buffer); if (!Arrays.equals(buffer, WaveUtils.CHUNK_DATA)) { throw new IOException("Unexpected chunk - expecting data chunk"); } //Get data chunk size mInputStream.read(buffer); mDataByteSize = ByteBuffer.wrap(buffer).order(ByteOrder.LITTLE_ENDIAN).asIntBuffer().get(); } public void read() throws IOException { long start = System.currentTimeMillis(); long samplesRead = 0; int totalBytesRead = 0; while (totalBytesRead < mDataByteSize) { int bytesRead = mInputStream.read(mDataBuffer); totalBytesRead += bytesRead; float[] samples = ConversionUtils.convertFromSigned16BitSamples(mDataBuffer); if (bytesRead != mDataBuffer.length) { samples = Arrays.copyOf(samples, bytesRead / 2); } if (mRealTime) { samplesRead += samples.length; long actualElapsed = System.currentTimeMillis() - start; long audioElapsed = (long) (((double) samplesRead / 8000.0) * 1000.0); if (audioElapsed > actualElapsed) { try { Thread.sleep(audioElapsed - actualElapsed); } catch (InterruptedException e) { } } } if (mListener != null) { mListener.receive(new RealBuffer(samples)); } } close(); } public void setListener(Listener<RealBuffer> listener) { mListener = listener; } /** * Closes the file */ public void close() throws IOException { if (mInputStream != null) { mInputStream.close(); } } public static void main(String[] args) { Path path = Paths.get("/home/denny/Music/PCM.wav"); mLog.debug("Opening: " + path.toString()); try { MonoWaveReader reader = new MonoWaveReader(path, true); reader.setListener(new Listener<RealBuffer>() { @Override public void receive(RealBuffer realBuffer) { mLog.debug("Received buffer"); } }); reader.read(); } catch (IOException e) { mLog.error("Error", e); } mLog.debug("Finished"); } }