1 /*
2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.media.sound;
27
28 import java.io.IOException;
29 import java.util.Objects;
30 import java.util.Vector;
31
32 import javax.sound.sampled.AudioFormat;
33 import javax.sound.sampled.AudioInputStream;
34 import javax.sound.sampled.AudioSystem;
35
36
37 /**
38 * A-law encodes linear data, and decodes a-law data to linear data.
39 *
40 * @author Kara Kytle
41 */
42 public final class AlawCodec extends SunCodec {
43
44 /* Tables used for A-law decoding */
45
46 private static final byte[] ALAW_TABH = new byte[256];
47 private static final byte[] ALAW_TABL = new byte[256];
48
49 private static final AudioFormat.Encoding[] alawEncodings = { AudioFormat.Encoding.ALAW, AudioFormat.Encoding.PCM_SIGNED };
50
51 private static final short seg_end [] = {0xFF, 0x1FF, 0x3FF,
52 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF};
53
54 /**
55 * Initializes the decode tables
56 */
57 static {
58 for (int i=0;i<256;i++) {
59 int input = i ^ 0x55;
60 int mantissa = (input & 0xf ) << 4;
61 int segment = (input & 0x70) >> 4;
62 int value = mantissa+8;
63
64 if(segment>=1)
65 value+=0x100;
66 if(segment>1)
67 value <<= (segment -1);
68
69 if( (input & 0x80)==0 )
70 value = -value;
71
72 ALAW_TABL[i] = (byte)value;
73 ALAW_TABH[i] = (byte)(value>>8);
74 }
75 }
76
77
78 /**
79 * Constructs a new ALAW codec object.
80 */
81 public AlawCodec() {
82
83 super(alawEncodings, alawEncodings);
84 }
85
86 // NEW CODE
87
88 /**
89 */
90 public AudioFormat.Encoding[] getTargetEncodings(AudioFormat sourceFormat){
91
92 if( sourceFormat.getEncoding().equals( AudioFormat.Encoding.PCM_SIGNED )) {
93
94 if( sourceFormat.getSampleSizeInBits() == 16 ) {
95
96 AudioFormat.Encoding enc[] = new AudioFormat.Encoding[1];
97 enc[0] = AudioFormat.Encoding.ALAW;
98 return enc;
99
100 } else {
101 return new AudioFormat.Encoding[0];
102 }
103 } else if( sourceFormat.getEncoding().equals( AudioFormat.Encoding.ALAW ) ) {
104
105 if( sourceFormat.getSampleSizeInBits() == 8 ) {
106
107 AudioFormat.Encoding enc[] = new AudioFormat.Encoding[1];
108 enc[0] = AudioFormat.Encoding.PCM_SIGNED;
109 return enc;
110
111 } else {
112 return new AudioFormat.Encoding[0];
113 }
114
115 } else {
116 return new AudioFormat.Encoding[0];
117 }
118 }
119
120 /**
121 */
122 public AudioFormat[] getTargetFormats(AudioFormat.Encoding targetEncoding, AudioFormat sourceFormat){
123 Objects.requireNonNull(sourceFormat);
124 if( (targetEncoding.equals( AudioFormat.Encoding.PCM_SIGNED ) && sourceFormat.getEncoding().equals( AudioFormat.Encoding.ALAW)) ||
125 (targetEncoding.equals( AudioFormat.Encoding.ALAW) && sourceFormat.getEncoding().equals( AudioFormat.Encoding.PCM_SIGNED)) ) {
126 return getOutputFormats( sourceFormat );
127 } else {
128 return new AudioFormat[0];
129 }
130 }
131
132 /**
133 */
134 public AudioInputStream getAudioInputStream(AudioFormat.Encoding targetEncoding, AudioInputStream sourceStream){
135 AudioFormat sourceFormat = sourceStream.getFormat();
136 AudioFormat.Encoding sourceEncoding = sourceFormat.getEncoding();
137
138 if( !isConversionSupported(targetEncoding,sourceStream.getFormat()) ) {
139 throw new IllegalArgumentException("Unsupported conversion: " + sourceStream.getFormat().toString() + " to " + targetEncoding.toString());
140 }
141 if( sourceEncoding.equals( targetEncoding ) ) {
142 return sourceStream;
143 }
144 AudioFormat targetFormat = null;
145 if( sourceEncoding.equals( AudioFormat.Encoding.ALAW ) &&
146 targetEncoding.equals( AudioFormat.Encoding.PCM_SIGNED ) ) {
147
148 targetFormat = new AudioFormat( targetEncoding,
149 sourceFormat.getSampleRate(),
150 16,
151 sourceFormat.getChannels(),
152 2*sourceFormat.getChannels(),
153 sourceFormat.getSampleRate(),
154 sourceFormat.isBigEndian());
155
156 } else if( sourceEncoding.equals( AudioFormat.Encoding.PCM_SIGNED ) &&
157 targetEncoding.equals( AudioFormat.Encoding.ALAW ) ) {
158
159 targetFormat = new AudioFormat( targetEncoding,
160 sourceFormat.getSampleRate(),
161 8,
162 sourceFormat.getChannels(),
163 sourceFormat.getChannels(),
164 sourceFormat.getSampleRate(),
165 false);
166 } else {
167 throw new IllegalArgumentException("Unsupported conversion: " + sourceStream.getFormat().toString() + " to " + targetEncoding.toString());
168 }
169 return getConvertedStream(targetFormat, sourceStream);
170 }
171
172 /**
173 * use old code...
174 */
175 public AudioInputStream getAudioInputStream(AudioFormat targetFormat, AudioInputStream sourceStream){
176 if (!isConversionSupported(targetFormat, sourceStream.getFormat()))
177 throw new IllegalArgumentException("Unsupported conversion: "
178 + sourceStream.getFormat().toString() + " to "
179 + targetFormat.toString());
180 return getConvertedStream( targetFormat, sourceStream );
181 }
182
183
184 // OLD CODE
185
186
187 /**
188 * Opens the codec with the specified parameters.
189 * @param stream stream from which data to be processed should be read
190 * @param outputFormat desired data format of the stream after processing
191 * @return stream from which processed data may be read
192 * @throws IllegalArgumentException if the format combination supplied is
193 * not supported.
194 */
195 /* public AudioInputStream getConvertedStream(AudioFormat outputFormat, AudioInputStream stream) { */
196 private AudioInputStream getConvertedStream(AudioFormat outputFormat, AudioInputStream stream) {
197
198 AudioInputStream cs = null;
199 AudioFormat inputFormat = stream.getFormat();
200
201 if( inputFormat.matches(outputFormat) ) {
202 cs = stream;
203 } else {
204 cs = (AudioInputStream) (new AlawCodecStream(stream, outputFormat));
205 }
206
207 return cs;
208 }
209
210 /**
211 * Obtains the set of output formats supported by the codec
212 * given a particular input format.
213 * If no output formats are supported for this input format,
214 * returns an array of length 0.
215 * @return array of supported output formats.
216 */
217 /* public AudioFormat[] getOutputFormats(AudioFormat inputFormat) { */
218 private AudioFormat[] getOutputFormats(AudioFormat inputFormat) {
219
220
221 Vector<AudioFormat> formats = new Vector<>();
222 AudioFormat format;
223
224 if (inputFormat.getSampleSizeInBits() == 16
225 && AudioFormat.Encoding.PCM_SIGNED.equals(inputFormat.getEncoding())) {
226 format = new AudioFormat(AudioFormat.Encoding.ALAW,
227 inputFormat.getSampleRate(), 8,
228 inputFormat.getChannels(),
229 inputFormat.getChannels(),
230 inputFormat.getSampleRate(), false);
231 formats.addElement(format);
232 }
233 if (inputFormat.getSampleSizeInBits() == 8
234 && AudioFormat.Encoding.ALAW.equals(inputFormat.getEncoding())) {
235 format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
236 inputFormat.getSampleRate(), 16,
237 inputFormat.getChannels(),
238 inputFormat.getChannels() * 2,
239 inputFormat.getSampleRate(), false);
240 formats.addElement(format);
241 format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
242 inputFormat.getSampleRate(), 16,
243 inputFormat.getChannels(),
244 inputFormat.getChannels() * 2,
245 inputFormat.getSampleRate(), true);
246 formats.addElement(format);
247 }
248
249 AudioFormat[] formatArray = new AudioFormat[formats.size()];
250 for (int i = 0; i < formatArray.length; i++) {
251 formatArray[i] = formats.elementAt(i);
252 }
253 return formatArray;
254 }
255
256
257 private final class AlawCodecStream extends AudioInputStream {
258
259 // tempBuffer required only for encoding (when encode is true)
260 private static final int tempBufferSize = 64;
261 private byte tempBuffer [] = null;
262
263 /**
264 * True to encode to a-law, false to decode to linear
265 */
266 boolean encode = false;
267
268 AudioFormat encodeFormat;
269 AudioFormat decodeFormat;
270
271 byte tabByte1[] = null;
272 byte tabByte2[] = null;
273 int highByte = 0;
274 int lowByte = 1;
275
276 AlawCodecStream(AudioInputStream stream, AudioFormat outputFormat) {
277
278 super(stream, outputFormat, -1);
279
280 AudioFormat inputFormat = stream.getFormat();
281
282 // throw an IllegalArgumentException if not ok
283 if ( ! (isConversionSupported(outputFormat, inputFormat)) ) {
284
285 throw new IllegalArgumentException("Unsupported conversion: " + inputFormat.toString() + " to " + outputFormat.toString());
286 }
287
288 //$$fb 2002-07-18: fix for 4714846: JavaSound ULAW (8-bit) encoder erroneously depends on endian-ness
289 boolean PCMIsBigEndian;
290
291 // determine whether we are encoding or decoding
292 if (AudioFormat.Encoding.ALAW.equals(inputFormat.getEncoding())) {
293 encode = false;
294 encodeFormat = inputFormat;
295 decodeFormat = outputFormat;
296 PCMIsBigEndian = outputFormat.isBigEndian();
297 } else {
298 encode = true;
299 encodeFormat = outputFormat;
300 decodeFormat = inputFormat;
301 PCMIsBigEndian = inputFormat.isBigEndian();
302 tempBuffer = new byte[tempBufferSize];
303 }
304
305 if (PCMIsBigEndian) {
306 tabByte1 = ALAW_TABH;
307 tabByte2 = ALAW_TABL;
308 highByte = 0;
309 lowByte = 1;
310 } else {
311 tabByte1 = ALAW_TABL;
312 tabByte2 = ALAW_TABH;
313 highByte = 1;
314 lowByte = 0;
315 }
316
317 // set the AudioInputStream length in frames if we know it
318 if (stream instanceof AudioInputStream) {
319 frameLength = stream.getFrameLength();
320 }
321
322 // set framePos to zero
323 framePos = 0;
324 frameSize = inputFormat.getFrameSize();
325 if( frameSize==AudioSystem.NOT_SPECIFIED ) {
326 frameSize=1;
327 }
328 }
329
330
331 /*
332 * $$jb 2/23/99
333 * Used to determine segment number in aLaw encoding
334 */
335 private short search(short val, short table[], short size) {
336 for(short i = 0; i < size; i++) {
337 if (val <= table[i]) { return i; }
338 }
339 return size;
340 }
341
342 /**
343 * Note that this won't actually read anything; must read in
344 * two-byte units.
345 */
346 public int read() throws IOException {
347
348 byte[] b = new byte[1];
349 return read(b, 0, b.length);
350 }
351
352
353 public int read(byte[] b) throws IOException {
354
355 return read(b, 0, b.length);
356 }
357
358 public int read(byte[] b, int off, int len) throws IOException {
359
360 // don't read fractional frames
361 if( len%frameSize != 0 ) {
362 len -= (len%frameSize);
363 }
364
365 if (encode) {
366
367 short QUANT_MASK = 0xF;
368 short SEG_SHIFT = 4;
369 short mask;
370 short seg;
371 int adj;
372 int i;
373
374 short sample;
375 byte enc;
376
377 int readCount = 0;
378 int currentPos = off;
379 int readLeft = len*2;
380 int readLen = ( (readLeft>tempBufferSize) ? tempBufferSize : readLeft );
381
382 while ((readCount = super.read(tempBuffer,0,readLen))>0) {
383
384 for (i = 0; i < readCount; i+=2) {
385
386 /* Get the sample from the tempBuffer */
387 sample = (short)(( (tempBuffer[i + highByte]) << 8) & 0xFF00);
388 sample |= (short)( (tempBuffer[i + lowByte]) & 0xFF);
389
390 if(sample >= 0) {
391 mask = 0xD5;
392 } else {
393 mask = 0x55;
394 sample = (short)(-sample - 8);
395 }
396 /* Convert the scaled magnitude to segment number. */
397 seg = search(sample, seg_end, (short) 8);
398 /*
399 * Combine the sign, segment, quantization bits
400 */
401 if (seg >= 8) { /* out of range, return maximum value. */
402 enc = (byte) (0x7F ^ mask);
403 } else {
404 enc = (byte) (seg << SEG_SHIFT);
405 if(seg < 2) {
406 enc |= (byte) ( (sample >> 4) & QUANT_MASK);
407 } else {
408 enc |= (byte) ( (sample >> (seg + 3)) & QUANT_MASK );
409 }
410 enc ^= mask;
411 }
412 /* Now put the encoded sample where it belongs */
413 b[currentPos] = enc;
414 currentPos++;
415 }
416 /* And update pointers and counters for next iteration */
417 readLeft -= readCount;
418 readLen = ( (readLeft>tempBufferSize) ? tempBufferSize : readLeft );
419 }
420
421 if( currentPos==off && readCount<0 ) { // EOF or error
422 return readCount;
423 }
424
425 return (currentPos - off); /* Number of bytes written to new buffer */
426
427 } else {
428
429 int i;
430 int readLen = len/2;
431 int readOffset = off + len/2;
432 int readCount = super.read(b, readOffset, readLen);
433
434 for (i = off; i < (off + (readCount*2)); i+=2) {
435 b[i] = tabByte1[b[readOffset] & 0xFF];
436 b[i+1] = tabByte2[b[readOffset] & 0xFF];
437 readOffset++;
438 }
439
440 if( readCount<0 ) { // EOF or error
441 return readCount;
442 }
443
444 return (i - off);
445 }
446 }
447
448 @Override
449 public long skip(final long n) throws IOException {
450 // Implementation of this method assumes that we support
451 // encoding/decoding from/to 8/16 bits only
452 return encode ? super.skip(n * 2) / 2 : super.skip(n / 2) * 2;
453 }
454 } // end class AlawCodecStream
455 } // end class ALAW