aboutsummaryrefslogtreecommitdiff
path: root/sound/audiostream.cpp
blob: 8b92f4f30e4314093b37380581ecb9093f22d404 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
/* ScummVM - Scumm Interpreter
 * Copyright (C) 2001-2006 The ScummVM project
 *
 * 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 2
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

#include "common/stdafx.h"
#include "common/endian.h"
#include "common/file.h"
#include "common/list.h"
#include "common/util.h"

#include "sound/audiostream.h"
#include "sound/mixer.h"
#include "sound/mp3.h"
#include "sound/vorbis.h"
#include "sound/flac.h"


// This used to be an inline template function, but
// buggy template function handling in MSVC6 forced
// us to go with the macro approach. So far this is
// the only template function that MSVC6 seemed to
// compile incorrectly. Knock on wood.
#define READ_ENDIAN_SAMPLE(is16Bit, isUnsigned, ptr, isLE) \
	((is16Bit ? (isLE ? READ_LE_UINT16(ptr) : READ_BE_UINT16(ptr)) : (*ptr << 8)) ^ (isUnsigned ? 0x8000 : 0))


namespace Audio {

struct StreamFileFormat {
	/** Decodername */
	const char* decoderName;
	const char* fileExtension;
	/**
	 * Pointer to a function which tries to open a file of type StreamFormat.
	 * Return NULL in case of an error (invalid/nonexisting file).
	 */
	AudioStream* (*openStreamFile)(Common::SeekableReadStream *stream, bool disposeAfterUse,
					uint32 startTime, uint32 duration, uint numLoops);
};

static const StreamFileFormat STREAM_FILEFORMATS[] = {
	/* decoderName,		fileExt, openStreamFuntion */
#ifdef USE_FLAC
	{ "Flac",			".flac", makeFlacStream },
	{ "Flac",			".fla",  makeFlacStream },
#endif
#ifdef USE_VORBIS
	{ "Ogg Vorbis",		".ogg",  makeVorbisStream },
#endif
#ifdef USE_MAD
	{ "MPEG Layer 3",	".mp3",  makeMP3Stream },
#endif

	{ NULL, NULL, NULL } // Terminator
};

AudioStream* AudioStream::openStreamFile(const Common::String &basename, uint32 startTime, uint32 duration, uint numLoops) {
	AudioStream* stream = NULL;
	Common::File *fileHandle = new Common::File();

	for (int i = 0; i < ARRAYSIZE(STREAM_FILEFORMATS)-1 && stream == NULL; ++i) {
		Common::String filename = basename + STREAM_FILEFORMATS[i].fileExtension;
		fileHandle->open(filename);
		if (fileHandle->isOpen()) {
			// Create the stream object
			stream = STREAM_FILEFORMATS[i].openStreamFile(fileHandle, true, startTime, duration, numLoops);
			fileHandle = 0;
			break;
		}
	}

	delete fileHandle;

	if (stream == NULL) {
		debug(1, "AudioStream: Could not open compressed AudioFile %s", basename.c_str());
	}

	return stream;
}

#pragma mark -
#pragma mark --- LinearMemoryStream ---
#pragma mark -


/**
 * A simple raw audio stream, purely memory based. It operates on a single
 * block of data, which is passed to it upon creation.
 * Optionally supports looping the sound.
 *
 * Design note: This code tries to be as efficient as possible (without
 * resorting to assembly, that is). To this end, it is written as a template
 * class. This way the compiler can create optimized code for each special
 * case. This results in a total of 12 versions of the code being generated.
 */
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
class LinearMemoryStream : public AudioStream {
protected:
	const byte *_ptr;
	const byte *_end;
	const byte *_loopPtr;
	const byte *_loopEnd;
	const int _rate;
	const byte *_origPtr;

public:
	LinearMemoryStream(int rate, const byte *ptr, uint len, uint loopOffset, uint loopLen, bool autoFreeMemory)
		: _ptr(ptr), _end(ptr+len), _loopPtr(0), _loopEnd(0), _rate(rate) {

		// Verify the buffer sizes are sane
		if (is16Bit && stereo)
			assert((len & 3) == 0 && (loopLen & 3) == 0);
		else if (is16Bit || stereo)
			assert((len & 1) == 0 && (loopLen & 1) == 0);

		if (loopLen) {
			_loopPtr = _ptr + loopOffset;
			_loopEnd = _loopPtr + loopLen;
		}
		if (stereo)	// Stereo requires even sized data
			assert(len % 2 == 0);

		_origPtr = autoFreeMemory ? ptr : 0;
	}
	~LinearMemoryStream() {
		free(const_cast<byte *>(_origPtr));
	}
	int readBuffer(int16 *buffer, const int numSamples);

	bool isStereo() const		{ return stereo; }
	bool endOfData() const		{ return _ptr >= _end; }

	int getRate() const			{ return _rate; }
};

template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
int LinearMemoryStream<stereo, is16Bit, isUnsigned, isLE>::readBuffer(int16 *buffer, const int numSamples) {
	int samples = 0;
	while (samples < numSamples && _ptr < _end) {
		const int len = MIN(numSamples, samples + (int)(_end - _ptr) / (is16Bit ? 2 : 1));
		while (samples < len) {
			*buffer++ = READ_ENDIAN_SAMPLE(is16Bit, isUnsigned, _ptr, isLE);
			_ptr += (is16Bit ? 2 : 1);
			samples++;
		}
		// Loop, if looping was specified
		if (_loopPtr && _ptr >= _end) {
			_ptr = _loopPtr;
			_end = _loopEnd;
		}
	}
	return samples;
}


#pragma mark -
#pragma mark --- Input stream factory ---
#pragma mark -

/* In the following, we use preprocessor / macro tricks to simplify the code
 * which instantiates the input streams. We used to use template functions for
 * this, but MSVC6 / EVC 3-4 (used for WinCE builds) are extremely buggy when it
 * comes to this feature of C++... so as a compromise we use macros to cut down
 * on the (source) code duplication a bit.
 * So while normally macro tricks are said to make maintenance harder, in this
 * particular case it should actually help it :-)
 */

#define MAKE_LINEAR(STEREO, UNSIGNED) \
		if (is16Bit) { \
			if (isLE) \
				return new LinearMemoryStream<STEREO, true, UNSIGNED, true>(rate, ptr, len, loopOffset, loopLen, autoFree); \
			else  \
				return new LinearMemoryStream<STEREO, true, UNSIGNED, false>(rate, ptr, len, loopOffset, loopLen, autoFree); \
		} else \
			return new LinearMemoryStream<STEREO, false, UNSIGNED, false>(rate, ptr, len, loopOffset, loopLen, autoFree)

AudioStream *makeLinearInputStream(const byte *ptr, uint32 len, int rate, byte flags, uint loopStart, uint loopEnd) {
	const bool isStereo   = (flags & Audio::Mixer::FLAG_STEREO) != 0;
	const bool is16Bit    = (flags & Audio::Mixer::FLAG_16BITS) != 0;
	const bool isUnsigned = (flags & Audio::Mixer::FLAG_UNSIGNED) != 0;
	const bool isLE       = (flags & Audio::Mixer::FLAG_LITTLE_ENDIAN) != 0;
	const bool autoFree   = (flags & Audio::Mixer::FLAG_AUTOFREE) != 0;

	uint loopOffset = 0, loopLen = 0;
	if (flags & Audio::Mixer::FLAG_LOOP) {
		if (loopEnd == 0)
			loopEnd = len;
		assert(loopStart <= loopEnd);
		assert(loopEnd <= len);
			
		loopOffset = loopStart;
		loopLen = loopEnd - loopStart;
	}

	if (isStereo) {
		if (isUnsigned) {
			MAKE_LINEAR(true, true);
		} else {
			MAKE_LINEAR(true, false);
		}
	} else {
		if (isUnsigned) {
			MAKE_LINEAR(false, true);
		} else {
			MAKE_LINEAR(false, false);
		}
	}
}


#pragma mark -
#pragma mark --- Appendable audio stream ---
#pragma mark -

struct Buffer {
	byte *start;
	byte *end;
};

/**
 * Wrapped memory stream.
 */
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
class AppendableMemoryStream : public AppendableAudioStream {
protected:

	// A mutex to avoid access problems (causing e.g. corruption of
	// the linked list) in thread aware environments.
	Common::Mutex _mutex;

	// List of all queueud buffers	
	Common::List<Buffer> _bufferQueue;

	// Position in the front buffer, if any
	bool _finalized;
	const int _rate;
	byte *_pos;

	inline bool eosIntern() const { return _bufferQueue.empty(); };
public:
	AppendableMemoryStream(int rate);
	~AppendableMemoryStream();
	int readBuffer(int16 *buffer, const int numSamples);

	bool isStereo() const		{ return stereo; }
	bool endOfStream() const	{ return _finalized && eosIntern(); }
	bool endOfData() const		{ return eosIntern(); }

	int getRate() const			{ return _rate; }

	void queueBuffer(byte *data, uint32 size);
	void finish()				{ _finalized = true; }
};

template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
AppendableMemoryStream<stereo, is16Bit, isUnsigned, isLE>::AppendableMemoryStream(int rate)
 : _finalized(false), _rate(rate), _pos(0) {

}

template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
AppendableMemoryStream<stereo, is16Bit, isUnsigned, isLE>::~AppendableMemoryStream() {
	// Clear the queue
	Common::List<Buffer>::iterator iter;
	for (iter = _bufferQueue.begin(); iter != _bufferQueue.end(); ++iter)
		delete[] iter->start;
}

template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
int AppendableMemoryStream<stereo, is16Bit, isUnsigned, isLE>::readBuffer(int16 *buffer, const int numSamples) {
	Common::StackLock lock(_mutex);

	int samples = 0;
	while (samples < numSamples && !eosIntern()) {
		Buffer buf = *_bufferQueue.begin();
		if (_pos == 0)
			_pos = buf.start;

		assert(buf.start <= _pos && _pos <= buf.end);
		const int samplesLeftInCurBuffer = buf.end - _pos;
		if (samplesLeftInCurBuffer == 0) {
			delete [] buf.start;
			_bufferQueue.erase(_bufferQueue.begin());
			_pos = 0;
			continue;
		}

		const int len = MIN(numSamples, samples + samplesLeftInCurBuffer / (is16Bit ? 2 : 1));
		while (samples < len) {
			*buffer++ = READ_ENDIAN_SAMPLE(is16Bit, isUnsigned, _pos, isLE);
			_pos += (is16Bit ? 2 : 1);
			samples++;
		}
	}

	return samples;
}

template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
void AppendableMemoryStream<stereo, is16Bit, isUnsigned, isLE>::queueBuffer(byte *data, uint32 size) {
	Common::StackLock lock(_mutex);

	// Verify the buffer size is sane
	if (is16Bit && stereo)
		assert((size & 3) == 0);
	else if (is16Bit || stereo)
		assert((size & 1) == 0);

	// Verify that the stream has not yet been finalized (by a call to finish())
	assert(!_finalized);

	// Queue the buffer
	Buffer buf = {data, data+size};
	_bufferQueue.push_back(buf);


#if 0
	// Output some stats
	uint totalSize = 0;
	Common::List<Buffer>::iterator iter;
	for (iter = _bufferQueue.begin(); iter != _bufferQueue.end(); ++iter)
		totalSize += iter->end - iter->start;
	printf("AppendableMemoryStream::queueBuffer: added a %d byte buf, a total of %d bytes are queued\n",
				size, totalSize);
#endif
}


#define MAKE_WRAPPED(STEREO, UNSIGNED) \
		if (is16Bit) { \
			if (isLE) \
				return new AppendableMemoryStream<STEREO, true, UNSIGNED, true>(rate); \
			else  \
				return new AppendableMemoryStream<STEREO, true, UNSIGNED, false>(rate); \
		} else \
			return new AppendableMemoryStream<STEREO, false, UNSIGNED, false>(rate)

AppendableAudioStream *makeAppendableAudioStream(int rate, byte _flags) {
	const bool isStereo = (_flags & Audio::Mixer::FLAG_STEREO) != 0;
	const bool is16Bit = (_flags & Audio::Mixer::FLAG_16BITS) != 0;
	const bool isUnsigned = (_flags & Audio::Mixer::FLAG_UNSIGNED) != 0;
	const bool isLE       = (_flags & Audio::Mixer::FLAG_LITTLE_ENDIAN) != 0;

	if (isStereo) {
		if (isUnsigned) {
			MAKE_WRAPPED(true, true);
		} else {
			MAKE_WRAPPED(true, false);
		}
	} else {
		if (isUnsigned) {
			MAKE_WRAPPED(false, true);
		} else {
			MAKE_WRAPPED(false, false);
		}
	}
}


} // End of namespace Audio