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Java Source | 1997-01-27 | 11.3 KB | 408 lines |
- /*
- * @(#)AudioDevice.java 1.4 96/03/12 Arthur van Hoff, Thomas Ball
- *
- * Copyright (c) 1994, 1995 Sun Microsystems, Inc. All Rights Reserved.
- *
- * Permission to use, copy, modify, and distribute this software
- * and its documentation for NON-COMMERCIAL purposes and without
- * fee is hereby granted provided that this copyright notice
- * appears in all copies. Please refer to the file "copyright.html"
- * for further important copyright and licensing information.
- *
- * SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
- * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
- * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
- * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
- * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
- * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
- */
-
- package sun.audio;
-
- import java.util.Vector;
- import java.util.Enumeration;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.OutputStream;
-
- /**
- * This class provides an interface to a Sun audio device.
- *
- * This class emulates systems with multiple audio channels, mixing
- * multiple streams for the workstation's single-channel device.
- *
- * @see AudioData
- * @see AudioDataStream
- * @see AudioStream
- * @see AudioStreamSequence
- * @see ContinuousAudioDataStream
- * @author Arthur van Hoff, Thomas Ball
- * @version 1.2, 23 Aug 1995
- */
- public class AudioDevice {
-
- private Vector streams;
- private byte ulaw[];
- private int linear[];
- private int dev;
-
- /*
- * ulaw stuff
- */
- private static final int MSCLICK = 50;
- private static final int MSMARGIN = MSCLICK / 3;
- private static final int BYTES_PER_SAMPLE = 1;
- private static final int SAMPLE_RATE = 8000;
-
- /* define the add-in bias for 16 bit samples */
- private final static int ULAW_BIAS = 0x84;
- private final static int ULAW_CLIP = 32635;
-
- private final static int ULAW_TAB[] = {
- -32124, -31100, -30076, -29052, -28028, -27004, -25980, -24956,
- -23932, -22908, -21884, -20860, -19836, -18812, -17788, -16764,
- -15996, -15484, -14972, -14460, -13948, -13436, -12924, -12412,
- -11900, -11388, -10876, -10364, -9852, -9340, -8828, -8316,
- -7932, -7676, -7420, -7164, -6908, -6652, -6396, -6140,
- -5884, -5628, -5372, -5116, -4860, -4604, -4348, -4092,
- -3900, -3772, -3644, -3516, -3388, -3260, -3132, -3004,
- -2876, -2748, -2620, -2492, -2364, -2236, -2108, -1980,
- -1884, -1820, -1756, -1692, -1628, -1564, -1500, -1436,
- -1372, -1308, -1244, -1180, -1116, -1052, -988, -924,
- -876, -844, -812, -780, -748, -716, -684, -652,
- -620, -588, -556, -524, -492, -460, -428, -396,
- -372, -356, -340, -324, -308, -292, -276, -260,
- -244, -228, -212, -196, -180, -164, -148, -132,
- -120, -112, -104, -96, -88, -80, -72, -64,
- -56, -48, -40, -32, -24, -16, -8, 0,
- 32124, 31100, 30076, 29052, 28028, 27004, 25980, 24956,
- 23932, 22908, 21884, 20860, 19836, 18812, 17788, 16764,
- 15996, 15484, 14972, 14460, 13948, 13436, 12924, 12412,
- 11900, 11388, 10876, 10364, 9852, 9340, 8828, 8316,
- 7932, 7676, 7420, 7164, 6908, 6652, 6396, 6140,
- 5884, 5628, 5372, 5116, 4860, 4604, 4348, 4092,
- 3900, 3772, 3644, 3516, 3388, 3260, 3132, 3004,
- 2876, 2748, 2620, 2492, 2364, 2236, 2108, 1980,
- 1884, 1820, 1756, 1692, 1628, 1564, 1500, 1436,
- 1372, 1308, 1244, 1180, 1116, 1052, 988, 924,
- 876, 844, 812, 780, 748, 716, 684, 652,
- 620, 588, 556, 524, 492, 460, 428, 396,
- 372, 356, 340, 324, 308, 292, 276, 260,
- 244, 228, 212, 196, 180, 164, 148, 132,
- 120, 112, 104, 96, 88, 80, 72, 64,
- 56, 48, 40, 32, 24, 16, 8, 0
- };
- private final static int ULAW_LUT[] = {
- 0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
- 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
- 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
- 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
- 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
- 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
- 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
- 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
- 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
- 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
- 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
- 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
- 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
- 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7
- };
-
- private native int audioOpen();
- private native void audioClose();
- private synchronized native void audioWrite(byte buf[], int len);
-
- /**
- * The default audio player. This audio player is initialized
- * automatically.
- */
- public static final AudioDevice device = new AudioDevice();
-
- /**
- * Create an AudioDevice instance.
- */
- private AudioDevice() {
- try {
- System.loadLibrary("msawt");
- } catch (UnsatisfiedLinkError e) {
- System.out.println("could not find/load the mmedia library");
- }
-
- streams = new Vector();
- int bufferSize = ((SAMPLE_RATE * MSCLICK) / 1000) * BYTES_PER_SAMPLE;
- ulaw = new byte[bufferSize];
- linear = new int[bufferSize];
- }
-
- /**
- * Open an audio channel.
- */
- public synchronized void openChannel(InputStream in) {
- streams.insertElementAt(in, 0);
- notify();
- }
-
- /**
- * Close an audio channel.
- */
- public synchronized void closeChannel(InputStream in) {
- if (streams.removeElement(in)) {
- try {
- in.close();
- } catch (IOException e) {
- }
- }
- }
-
- /**
- * Open the device (done automatically)
- */
- public synchronized void open() {
- int ntries = 1;
- int maxtries = 5;
- while (dev == 0) {
- dev = audioOpen();
- if (dev < 0) {
- System.out.println("no audio device");
- return;
- }
- if (dev == 0) {
- System.out.println("audio device busy (attempt " + ntries +
- " out of " + maxtries + ")");
- if ((streams.size() == 0) || (++ntries > maxtries)) {
- // failed to open the device
- // close all open streams, wait a while and return
- closeStreams();
- return;
- }
-
- // use wait instead of sleep because this unlocks the
- // current object during the wait.
- try {
- wait(3000);
- } catch (InterruptedException e) {
- closeStreams();
- return;
- }
- }
- }
- }
-
- /**
- * Close the device (done automatically)
- */
- public synchronized void close() {
- if (dev != 0) {
- audioClose();
- dev = 0;
- }
- closeStreams();
- }
-
- /**
- * Play one mixed click of data
- */
- private synchronized void mix() {
- int len = ulaw.length;
- byte ubuf[] = ulaw;
-
- switch (streams.size()) {
- case 0: {
- // fill the buffer with silence
- for (int n = len ; n-- > 0 ;) {
- ubuf[n] = 127;
- }
- break;
- }
-
- case 1: {
- // read from the input stream
- InputStream in = (InputStream)streams.elementAt(0);
- int n = 0;
- try {
- n = in.read(ubuf, 0, len);
- } catch (IOException e) {
- n = -1;
- }
-
- // Close the stream if needed
- if (n <= 0) {
- streams.removeElementAt(0);
- n = 0;
- try {
- in.close();
- } catch (IOException e) {
- }
- }
-
- // fill the rest of the buffer with silence
- for (; n < len ; n++) {
- ubuf[n] = 127;
- }
- break;
- }
-
- default: {
- int tab[] = ULAW_TAB;
- int lbuf[] = linear;
- int i = streams.size() - 1;
-
- // fill linear buffer with the first stream
- InputStream in = (InputStream)streams.elementAt(i);
- int n = 0;
- try {
- n = in.read(ubuf, 0, len);
- } catch (IOException e) {
- n = -1;
- }
-
- // Close the stream if needed
- if (n <= 0) {
- streams.removeElementAt(i);
- n = 0;
- try {
- in.close();
- } catch (IOException e) {
- }
-
- }
-
- // copy the data into the linear buffer
- for (int j = 0 ; j < n ; j++) {
- lbuf[j] = tab[ubuf[j] & 0xFF];
- }
-
- // zero the rest of the buffer.
- for (; n < len ; n++) {
- lbuf[n] = 0;
- }
-
- // mix the rest of the streams into the linear buffer
- while (i-- > 0) {
- in = (InputStream)streams.elementAt(i);
- try {
- n = in.read(ubuf, 0, len);
- } catch (IOException e) {
- n = -1;
- }
- if (n <= 0) {
- streams.removeElementAt(i);
- n = 0;
- try {
- in.close();
- } catch (IOException e) {
- }
- }
- while (n-- > 0) {
- lbuf[n] += tab[ubuf[n] & 0xFF];
- }
- }
-
- // convert the linear buffer back to ulaw
- int lut[] = ULAW_LUT;
- for (n = len ; n-- > 0 ; ) {
- int sample = lbuf[n];
-
- /* Get the sample into sign-magnitude. */
- if (sample >= 0) {
- if (sample > ULAW_CLIP) {
- sample = ULAW_CLIP; /* clip the magnitude */
- }
-
- /* Convert from 16 bit linear to ulaw. */
- sample += ULAW_BIAS;
- int exponent = lut[sample >> 7];
- int mantissa = (sample >> (exponent + 3)) & 0x0F;
- sample = ((exponent << 4) | mantissa) ^ 0xFF;
- } else {
- sample = -sample;
- if (sample > ULAW_CLIP) {
- sample = ULAW_CLIP; /* clip the magnitude */
- }
-
- /* Convert from 16 bit linear to ulaw. */
- sample += ULAW_BIAS;
- int exponent = lut[sample >> 7];
- int mantissa = (sample >> (exponent + 3)) & 0x0F;
- sample = ((exponent << 4) | mantissa) ^ 0x7F;
- }
- ubuf[n] = (byte)sample;
- }
- }
- }
-
- }
-
- /**
- * Wait for data
- */
- private synchronized boolean waitForData() throws InterruptedException {
- if (streams.size() == 0) {
- close();
- wait();
- open();
- return true;
- }
- return false;
- }
-
- /**
- * Play open audio stream(s)
- */
- public void play() {
- try {
- long tm = System.currentTimeMillis() - MSMARGIN;
-
- while (dev > 0) {
- // wait for data
- if (waitForData()) {
- tm = System.currentTimeMillis() - MSMARGIN;
- }
-
- // mix the next bit
- mix();
-
- // write the next buffer
- audioWrite(ulaw, ulaw.length);
-
- // wait for the time out
- tm += MSCLICK;
- long delay = tm - System.currentTimeMillis();
- if (delay > 0) {
- Thread.currentThread().sleep(delay);
- } else {
- // We've lost it, reset the time..
- //System.out.println("delay2=" + delay);
- tm = System.currentTimeMillis() - MSMARGIN;
- }
- }
- } catch (InterruptedException e) {
- // the thread got interrupted, exit
- }
- }
-
- /**
- * Close streams
- */
- public synchronized void closeStreams() {
- // close the streams be garbage collected
- for (Enumeration e = streams.elements() ; e.hasMoreElements() ; ) {
- try {
- ((InputStream)e.nextElement()).close();
- } catch (IOException ee) {
- }
- }
- streams = new Vector();
- }
-
- /**
- * Number of channels currently open.
- */
- public int openChannels() {
- return streams.size();
- }
- }
-