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/* 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/endian.h"
#include "common/stream.h"
#include "sound/audiostream.h"
#include "sound/mixer.h"
#include "sound/raw.h"
namespace Audio {
// 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))
// TODO: Get rid of this
uint32 calculateSampleOffset(const Timestamp &where, int rate) {
return where.convertToFramerate(rate).totalNumberOfFrames();
}
#pragma mark -
#pragma mark --- RawMemoryStream ---
#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 RawMemoryStream : public SeekableAudioStream {
protected:
const byte *_ptr;
const byte *_end;
const int _rate;
const byte *_origPtr;
const DisposeAfterUse::Flag _disposeAfterUse;
const Timestamp _playtime;
public:
RawMemoryStream(int rate, const byte *ptr, uint len, DisposeAfterUse::Flag autoFreeMemory)
: _ptr(ptr), _end(ptr+len), _rate(rate), _origPtr(ptr),
_disposeAfterUse(autoFreeMemory),
_playtime(0, len / (is16Bit ? 2 : 1) / (stereo ? 2 : 1), rate) {
}
virtual ~RawMemoryStream() {
if (_disposeAfterUse == DisposeAfterUse::YES)
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; }
bool seek(const Timestamp &where);
Timestamp getLength() const { return _playtime; }
};
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
int RawMemoryStream<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);
}
return numSamples-samples;
}
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
bool RawMemoryStream<stereo, is16Bit, isUnsigned, isLE>::seek(const Timestamp &where) {
const uint8 *ptr = _origPtr + calculateSampleOffset(where, getRate()) * (is16Bit ? 2 : 1) * (stereo ? 2 : 1);
if (ptr > _end) {
_ptr = _end;
return false;
} else if (ptr == _end) {
_ptr = _end;
return true;
} else {
_ptr = ptr;
return true;
}
}
#pragma mark -
#pragma mark --- RawDiskStream ---
#pragma mark -
/**
* RawDiskStream. This can stream raw PCM audio data from disk. The
* function takes an pointer to an array of RawDiskStreamAudioBlock which defines the
* start position and length of each block of uncompressed audio in the stream.
*/
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
class RawDiskStream : public SeekableAudioStream {
// Allow backends to override buffer size
#ifdef CUSTOM_AUDIO_BUFFER_SIZE
static const int32 BUFFER_SIZE = CUSTOM_AUDIO_BUFFER_SIZE;
#else
static const int32 BUFFER_SIZE = 16384;
#endif
protected:
byte* _buffer; ///< Streaming buffer
const byte *_ptr; ///< Pointer to current position in stream buffer
const int _rate; ///< Sample rate of stream
Timestamp _playtime; ///< Calculated total play time
Common::SeekableReadStream *_stream; ///< Stream to read data from
int32 _filePos; ///< Current position in stream
int32 _diskLeft; ///< Samples left in stream in current block not yet read to buffer
int32 _bufferLeft; ///< Samples left in buffer in current block
const DisposeAfterUse::Flag _disposeAfterUse; ///< Indicates whether the stream object should be deleted when this RawDiskStream is destructed
RawDiskStreamAudioBlock *_audioBlock; ///< Audio block list
const int _audioBlockCount; ///< Number of blocks in _audioBlock
int _currentBlock; ///< Current audio block number
public:
RawDiskStream(int rate, DisposeAfterUse::Flag disposeStream, Common::SeekableReadStream *stream, RawDiskStreamAudioBlock *block, uint numBlocks)
: _rate(rate), _playtime(0, rate), _stream(stream), _disposeAfterUse(disposeStream),
_audioBlockCount(numBlocks) {
assert(numBlocks > 0);
// Allocate streaming buffer
if (is16Bit) {
_buffer = (byte *)malloc(BUFFER_SIZE * sizeof(int16));
} else {
_buffer = (byte *)malloc(BUFFER_SIZE * sizeof(byte));
}
_ptr = _buffer;
_bufferLeft = 0;
// Copy audio block data to our buffer
// TODO: Replace this with a Common::Array or Common::List to
// make it a little friendlier.
_audioBlock = new RawDiskStreamAudioBlock[numBlocks];
memcpy(_audioBlock, block, numBlocks * sizeof(RawDiskStreamAudioBlock));
// Set current buffer state, playing first block
_currentBlock = 0;
_filePos = _audioBlock[_currentBlock].pos;
_diskLeft = _audioBlock[_currentBlock].len;
// Add up length of all blocks in order to caluclate total play time
int len = 0;
for (int r = 0; r < _audioBlockCount; r++) {
len += _audioBlock[r].len;
}
_playtime = Timestamp(0, len / (is16Bit ? 2 : 1) / (stereo ? 2 : 1), rate);
}
virtual ~RawDiskStream() {
if (_disposeAfterUse == DisposeAfterUse::YES) {
delete _stream;
}
delete[] _audioBlock;
free(_buffer);
}
int readBuffer(int16 *buffer, const int numSamples);
bool isStereo() const { return stereo; }
bool endOfData() const { return (_currentBlock == _audioBlockCount - 1) && (_diskLeft == 0) && (_bufferLeft == 0); }
int getRate() const { return _rate; }
Timestamp getLength() const { return _playtime; }
bool seek(const Timestamp &where);
};
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
int RawDiskStream<stereo, is16Bit, isUnsigned, isLE>::readBuffer(int16 *buffer, const int numSamples) {
int oldPos = _stream->pos();
bool restoreFilePosition = false;
int samples = numSamples;
while (samples > 0 && ((_diskLeft > 0 || _bufferLeft > 0) || (_currentBlock != _audioBlockCount - 1)) ) {
// Output samples in the buffer to the output
int len = MIN<int>(samples, _bufferLeft);
samples -= len;
_bufferLeft -= len;
while (len > 0) {
*buffer++ = READ_ENDIAN_SAMPLE(is16Bit, isUnsigned, _ptr, isLE);
_ptr += (is16Bit ? 2 : 1);
len--;
}
// Have we now finished this block? If so, read the next block
if ((_bufferLeft == 0) && (_diskLeft == 0) && (_currentBlock != _audioBlockCount - 1)) {
// Next block
_currentBlock++;
_filePos = _audioBlock[_currentBlock].pos;
_diskLeft = _audioBlock[_currentBlock].len;
}
// Now read more data from disk if there is more to be read
if ((_bufferLeft == 0) && (_diskLeft > 0)) {
int32 readAmount = MIN(_diskLeft, BUFFER_SIZE);
_stream->seek(_filePos, SEEK_SET);
_stream->read(_buffer, readAmount * (is16Bit? 2: 1));
// Amount of data in buffer is now the amount read in, and
// the amount left to read on disk is decreased by the same amount
_bufferLeft = readAmount;
_diskLeft -= readAmount;
_ptr = (byte *)_buffer;
_filePos += readAmount * (is16Bit ? 2 : 1);
// Set this flag now we've used the file, it restores it's
// original position.
restoreFilePosition = true;
}
}
// In case calling code relies on the position of this stream staying
// constant, I restore the location if I've changed it. This is probably
// not necessary.
if (restoreFilePosition) {
_stream->seek(oldPos, SEEK_SET);
}
return numSamples - samples;
}
template<bool stereo, bool is16Bit, bool isUnsigned, bool isLE>
bool RawDiskStream<stereo, is16Bit, isUnsigned, isLE>::seek(const Timestamp &where) {
const uint32 seekSample = calculateSampleOffset(where, getRate()) * (stereo ? 2 : 1);
uint32 curSample = 0;
// Search for the disk block in which the specific sample is placed
_currentBlock = 0;
while (_currentBlock < _audioBlockCount) {
uint32 nextBlockSample = curSample + _audioBlock[_currentBlock].len;
if (nextBlockSample > seekSample)
break;
curSample = nextBlockSample;
++_currentBlock;
}
_filePos = 0;
_diskLeft = 0;
_bufferLeft = 0;
if (_currentBlock == _audioBlockCount) {
return ((seekSample - curSample) == (uint32)_audioBlock[_currentBlock - 1].len);
} else {
const uint32 offset = seekSample - curSample;
_filePos = _audioBlock[_currentBlock].pos + offset * (is16Bit ? 2 : 1);
_diskLeft = _audioBlock[_currentBlock].len - offset;
return true;
}
}
#pragma mark -
#pragma mark --- Raw stream factories ---
#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 RawMemoryStream<STEREO, true, UNSIGNED, true>(rate, ptr, len, autoFree); \
else \
return new RawMemoryStream<STEREO, true, UNSIGNED, false>(rate, ptr, len, autoFree); \
} else \
return new RawMemoryStream<STEREO, false, UNSIGNED, false>(rate, ptr, len, autoFree)
SeekableAudioStream *makeRawMemoryStream(const byte *ptr, uint32 len,
DisposeAfterUse::Flag autoFree,
int rate, byte flags) {
const bool isStereo = (flags & Audio::FLAG_STEREO) != 0;
const bool is16Bit = (flags & Audio::FLAG_16BITS) != 0;
const bool isUnsigned = (flags & Audio::FLAG_UNSIGNED) != 0;
const bool isLE = (flags & Audio::FLAG_LITTLE_ENDIAN) != 0;
// Verify the buffer sizes are sane
if (is16Bit && isStereo) {
assert((len & 3) == 0);
} else if (is16Bit || isStereo) {
assert((len & 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);
}
}
}
AudioStream *makeRawMemoryStream_OLD(const byte *ptr, uint32 len,
DisposeAfterUse::Flag autoFree,
int rate, byte flags,
uint loopStart, uint loopEnd) {
SeekableAudioStream *s = makeRawMemoryStream(ptr, len, autoFree, rate, flags);
if ((flags & Audio::FLAG_LOOP) != 0) {
const bool isStereo = (flags & Audio::FLAG_STEREO) != 0;
const bool is16Bit = (flags & Audio::FLAG_16BITS) != 0;
if (loopEnd == 0)
loopEnd = len;
assert(loopStart <= loopEnd);
assert(loopEnd <= len);
// Verify the buffer sizes are sane
if (is16Bit && isStereo)
assert((loopStart & 3) == 0 && (loopEnd & 3) == 0);
else if (is16Bit || isStereo)
assert((loopStart & 1) == 0 && (loopEnd & 1) == 0);
const uint32 extRate = s->getRate() * (is16Bit ? 2 : 1) * (isStereo ? 2 : 1);
return new SubLoopingAudioStream(s, 0, Timestamp(0, loopStart, extRate), Timestamp(0, loopEnd, extRate));
} else {
return s;
}
}
#define MAKE_LINEAR_DISK(STEREO, UNSIGNED) \
if (is16Bit) { \
if (isLE) \
return new RawDiskStream<STEREO, true, UNSIGNED, true>(rate, disposeStream, stream, block, numBlocks); \
else \
return new RawDiskStream<STEREO, true, UNSIGNED, false>(rate, disposeStream, stream, block, numBlocks); \
} else \
return new RawDiskStream<STEREO, false, UNSIGNED, false>(rate, disposeStream, stream, block, numBlocks)
SeekableAudioStream *makeRawDiskStream(Common::SeekableReadStream *stream, RawDiskStreamAudioBlock *block, int numBlocks,
int rate, byte flags, DisposeAfterUse::Flag disposeStream) {
const bool isStereo = (flags & Audio::FLAG_STEREO) != 0;
const bool is16Bit = (flags & Audio::FLAG_16BITS) != 0;
const bool isUnsigned = (flags & Audio::FLAG_UNSIGNED) != 0;
const bool isLE = (flags & Audio::FLAG_LITTLE_ENDIAN) != 0;
if (isStereo) {
if (isUnsigned) {
MAKE_LINEAR_DISK(true, true);
} else {
MAKE_LINEAR_DISK(true, false);
}
} else {
if (isUnsigned) {
MAKE_LINEAR_DISK(false, true);
} else {
MAKE_LINEAR_DISK(false, false);
}
}
}
} // End of namespace Audio
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