netscape-revival
sun-java/classsrc/sun/audio/AudioDevice.java
/*
* @(#)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;
import java.lang.SecurityManager;
/**
* 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 {
SecurityManager.setScopePermission();
System.loadLibrary("mm3230");
SecurityManager.resetScopePermission();
} 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();
}
}