scummvm/sound/audiostream.cpp
2009-05-23 23:49:47 +00:00

399 lines
12 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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/debug.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 -
inline int32 calculatePlayTime(int rate, int samples) {
int32 seconds = samples / rate;
int32 milliseconds = (1000 * (samples % rate)) / rate;
return seconds * 1000 + milliseconds;
}
/**
* 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;
const int32 _playtime;
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), _playtime(calculatePlayTime(rate, len / (is16Bit ? 2 : 1) / (stereo ? 2 : 1))) {
if (loopLen) {
_loopPtr = _ptr + loopOffset;
_loopEnd = _loopPtr + loopLen;
}
_origPtr = autoFreeMemory ? ptr : 0;
}
virtual ~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; }
int32 getTotalPlayTime() const { return _playtime; }
};
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
int LinearMemoryStream<stereo, is16Bit, isUnsigned, isLE>::readBuffer(int16 *buffer, const int numSamples) {
int samples = numSamples;
while (samples > 0 && _ptr < _end) {
int len = MIN(samples, (int)(_end - _ptr) / (is16Bit ? 2 : 1));
samples -= len;
do {
*buffer++ = READ_ENDIAN_SAMPLE(is16Bit, isUnsigned, _ptr, isLE);
_ptr += (is16Bit ? 2 : 1);
} while (--len);
// Loop, if looping was specified
if (_loopPtr && _ptr >= _end) {
_ptr = _loopPtr;
_end = _loopEnd;
}
}
return numSamples-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;
}
// Verify the buffer sizes are sane
if (is16Bit && isStereo) {
assert((len & 3) == 0 && (loopLen & 3) == 0);
} else if (is16Bit || isStereo) {
assert((len & 1) == 0 && (loopLen & 1) == 0);
}
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.
*/
class BaseAppendableMemoryStream : 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 queued 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:
BaseAppendableMemoryStream(int rate);
~BaseAppendableMemoryStream();
bool endOfStream() const { return _finalized && eosIntern(); }
bool endOfData() const { return eosIntern(); }
int getRate() const { return _rate; }
void finish() { _finalized = true; }
void queueBuffer(byte *data, uint32 size);
};
/**
* Wrapped memory stream.
*/
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
class AppendableMemoryStream : public BaseAppendableMemoryStream {
public:
AppendableMemoryStream(int rate) : BaseAppendableMemoryStream(rate) {}
bool isStereo() const { return stereo; }
int readBuffer(int16 *buffer, const int numSamples);
};
BaseAppendableMemoryStream::BaseAppendableMemoryStream(int rate)
: _finalized(false), _rate(rate), _pos(0) {
}
BaseAppendableMemoryStream::~BaseAppendableMemoryStream() {
// 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 = numSamples;
while (samples > 0 && !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;
}
int len = MIN(samples, samplesLeftInCurBuffer / (is16Bit ? 2 : 1));
samples -= len;
do {
*buffer++ = READ_ENDIAN_SAMPLE(is16Bit, isUnsigned, _pos, isLE);
_pos += (is16Bit ? 2 : 1);
} while (--len);
}
return numSamples - samples;
}
void BaseAppendableMemoryStream::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