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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 "sound/decoders/adpcm.h"
#include "sound/audiostream.h"
namespace Audio {
class ADPCMStream : public RewindableAudioStream {
protected:
Common::SeekableReadStream *_stream;
const DisposeAfterUse::Flag _disposeAfterUse;
const int32 _startpos;
const int32 _endpos;
const int _channels;
const uint32 _blockAlign;
uint32 _blockPos[2];
const int _rate;
struct {
// OKI/IMA
struct {
int32 last;
int32 stepIndex;
} ima_ch[2];
} _status;
virtual void reset();
int16 stepAdjust(byte);
public:
ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign);
~ADPCMStream();
virtual bool endOfData() const { return (_stream->eos() || _stream->pos() >= _endpos); }
virtual bool isStereo() const { return _channels == 2; }
virtual int getRate() const { return _rate; }
virtual bool rewind();
};
// Routines to convert 12 bit linear samples to the
// Dialogic or Oki ADPCM coding format aka VOX.
// See also <http://www.comptek.ru/telephony/tnotes/tt1-13.html>
//
// IMA ADPCM support is based on
// <http://wiki.multimedia.cx/index.php?title=IMA_ADPCM>
//
// In addition, also MS IMA ADPCM is supported. See
// <http://wiki.multimedia.cx/index.php?title=Microsoft_IMA_ADPCM>.
ADPCMStream::ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: _stream(stream),
_disposeAfterUse(disposeAfterUse),
_startpos(stream->pos()),
_endpos(_startpos + size),
_channels(channels),
_blockAlign(blockAlign),
_rate(rate) {
reset();
}
ADPCMStream::~ADPCMStream() {
if (_disposeAfterUse == DisposeAfterUse::YES)
delete _stream;
}
void ADPCMStream::reset() {
memset(&_status, 0, sizeof(_status));
_blockPos[0] = _blockPos[1] = _blockAlign; // To make sure first header is read
}
bool ADPCMStream::rewind() {
// TODO: Error checking.
reset();
_stream->seek(_startpos);
return true;
}
#pragma mark -
class Oki_ADPCMStream : public ADPCMStream {
public:
Oki_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {}
virtual int readBuffer(int16 *buffer, const int numSamples);
protected:
int16 decodeOKI(byte);
};
int Oki_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
int samples;
byte data;
assert(numSamples % 2 == 0);
for (samples = 0; samples < numSamples && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
data = _stream->readByte();
buffer[samples] = decodeOKI((data >> 4) & 0x0f);
buffer[samples + 1] = decodeOKI(data & 0x0f);
}
return samples;
}
static const int16 okiStepSize[49] = {
16, 17, 19, 21, 23, 25, 28, 31,
34, 37, 41, 45, 50, 55, 60, 66,
73, 80, 88, 97, 107, 118, 130, 143,
157, 173, 190, 209, 230, 253, 279, 307,
337, 371, 408, 449, 494, 544, 598, 658,
724, 796, 876, 963, 1060, 1166, 1282, 1411,
1552
};
// Decode Linear to ADPCM
int16 Oki_ADPCMStream::decodeOKI(byte code) {
int16 diff, E, samp;
E = (2 * (code & 0x7) + 1) * okiStepSize[_status.ima_ch[0].stepIndex] / 8;
diff = (code & 0x08) ? -E : E;
samp = _status.ima_ch[0].last + diff;
// Clip the values to +/- 2^11 (supposed to be 12 bits)
samp = CLIP<int16>(samp, -2048, 2047);
_status.ima_ch[0].last = samp;
_status.ima_ch[0].stepIndex += stepAdjust(code);
_status.ima_ch[0].stepIndex = CLIP<int32>(_status.ima_ch[0].stepIndex, 0, ARRAYSIZE(okiStepSize) - 1);
// * 16 effectively converts 12-bit input to 16-bit output
return samp * 16;
}
#pragma mark -
class Ima_ADPCMStream : public ADPCMStream {
protected:
int16 decodeIMA(byte code, int channel = 0); // Default to using the left channel/using one channel
public:
Ima_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
memset(&_status, 0, sizeof(_status));
}
virtual int readBuffer(int16 *buffer, const int numSamples);
};
int Ima_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
int samples;
byte data;
assert(numSamples % 2 == 0);
for (samples = 0; samples < numSamples && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
data = _stream->readByte();
buffer[samples] = decodeIMA((data >> 4) & 0x0f);
buffer[samples + 1] = decodeIMA(data & 0x0f, _channels == 2 ? 1 : 0);
}
return samples;
}
#pragma mark -
class Apple_ADPCMStream : public Ima_ADPCMStream {
protected:
// Apple QuickTime IMA ADPCM
int32 _streamPos[2];
int16 _buffer[2][2];
uint8 _chunkPos[2];
void reset() {
Ima_ADPCMStream::reset();
_chunkPos[0] = 0;
_chunkPos[1] = 0;
_streamPos[0] = 0;
_streamPos[1] = _blockAlign;
}
public:
Apple_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: Ima_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
_chunkPos[0] = 0;
_chunkPos[1] = 0;
_streamPos[0] = 0;
_streamPos[1] = _blockAlign;
}
virtual int readBuffer(int16 *buffer, const int numSamples);
};
int Apple_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
// Need to write at least one samples per channel
assert((numSamples % _channels) == 0);
// Current sample positions
int samples[2] = { 0, 0};
// Number of samples per channel
int chanSamples = numSamples / _channels;
for (int i = 0; i < _channels; i++) {
_stream->seek(_streamPos[i]);
while ((samples[i] < chanSamples) &&
// Last byte read and a new one needed
!((_stream->eos() || (_stream->pos() >= _endpos)) && (_chunkPos[i] == 0))) {
if (_blockPos[i] == _blockAlign) {
// 2 byte header per block
uint16 temp = _stream->readUint16BE();
// First 9 bits are the upper bits of the predictor
_status.ima_ch[i].last = (int16) (temp & 0xFF80);
// Lower 7 bits are the step index
_status.ima_ch[i].stepIndex = temp & 0x007F;
// Clip the step index
_status.ima_ch[i].stepIndex = CLIP<int32>(_status.ima_ch[i].stepIndex, 0, 88);
_blockPos[i] = 2;
}
if (_chunkPos[i] == 0) {
// Decode data
byte data = _stream->readByte();
_buffer[i][0] = decodeIMA(data & 0x0F, i);
_buffer[i][1] = decodeIMA(data >> 4, i);
}
// The original is interleaved block-wise, we want it sample-wise
buffer[_channels * samples[i] + i] = _buffer[i][_chunkPos[i]];
if (++_chunkPos[i] > 1) {
// We're about to decode the next byte, so advance the block position
_chunkPos[i] = 0;
_blockPos[i]++;
}
samples[i]++;
if (_channels == 2)
if (_blockPos[i] == _blockAlign)
// We're at the end of the block.
// Since the channels are interleaved, skip the next block
_stream->skip(MIN<uint32>(_blockAlign, _endpos - _stream->pos()));
_streamPos[i] = _stream->pos();
}
}
return samples[0] + samples[1];
}
#pragma mark -
class MSIma_ADPCMStream : public Ima_ADPCMStream {
public:
MSIma_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign, bool invertSamples = false)
: Ima_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign), _invertSamples(invertSamples) {
if (blockAlign == 0)
error("ADPCMStream(): blockAlign isn't specified for MS IMA ADPCM");
}
virtual int readBuffer(int16 *buffer, const int numSamples) {
if (_channels == 1)
return readBufferMSIMA1(buffer, numSamples);
else
return readBufferMSIMA2(buffer, numSamples);
}
int readBufferMSIMA1(int16 *buffer, const int numSamples);
int readBufferMSIMA2(int16 *buffer, const int numSamples);
private:
bool _invertSamples; // Some implementations invert the way samples are decoded
};
int MSIma_ADPCMStream::readBufferMSIMA1(int16 *buffer, const int numSamples) {
int samples = 0;
byte data;
assert(numSamples % 2 == 0);
while (samples < numSamples && !_stream->eos() && _stream->pos() < _endpos) {
if (_blockPos[0] == _blockAlign) {
// read block header
_status.ima_ch[0].last = _stream->readSint16LE();
_status.ima_ch[0].stepIndex = _stream->readSint16LE();
_blockPos[0] = 4;
}
for (; samples < numSamples && _blockPos[0] < _blockAlign && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
data = _stream->readByte();
_blockPos[0]++;
buffer[samples] = decodeIMA(_invertSamples ? (data >> 4) & 0x0f : data & 0x0f);
buffer[samples + 1] = decodeIMA(_invertSamples ? data & 0x0f : (data >> 4) & 0x0f);
}
}
return samples;
}
// Microsoft as usual tries to implement it differently. This method
// is used for stereo data.
int MSIma_ADPCMStream::readBufferMSIMA2(int16 *buffer, const int numSamples) {
int samples;
uint32 data;
int nibble;
byte k;
// TODO: Currently this implementation only supports
// reading a multiple of 16 samples at once. We might
// consider changing that so it could read an arbitrary
// sample pair count.
assert(numSamples % 16 == 0);
for (samples = 0; samples < numSamples && !_stream->eos() && _stream->pos() < _endpos;) {
for (int channel = 0; channel < 2; channel++) {
data = _stream->readUint32LE();
for (nibble = 0; nibble < 8; nibble++) {
k = ((data & 0xf0000000) >> 28);
buffer[samples + channel + nibble * 2] = decodeIMA(k);
data <<= 4;
}
}
samples += 16;
}
return samples;
}
#pragma mark -
static const int MSADPCMAdaptCoeff1[] = {
256, 512, 0, 192, 240, 460, 392
};
static const int MSADPCMAdaptCoeff2[] = {
0, -256, 0, 64, 0, -208, -232
};
static const int MSADPCMAdaptationTable[] = {
230, 230, 230, 230, 307, 409, 512, 614,
768, 614, 512, 409, 307, 230, 230, 230
};
class MS_ADPCMStream : public ADPCMStream {
protected:
struct ADPCMChannelStatus {
byte predictor;
int16 delta;
int16 coeff1;
int16 coeff2;
int16 sample1;
int16 sample2;
};
struct {
// MS ADPCM
ADPCMChannelStatus ch[2];
} _status;
void reset() {
ADPCMStream::reset();
memset(&_status, 0, sizeof(_status));
}
public:
MS_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
if (blockAlign == 0)
error("MS_ADPCMStream(): blockAlign isn't specified for MS ADPCM");
memset(&_status, 0, sizeof(_status));
}
virtual int readBuffer(int16 *buffer, const int numSamples);
protected:
int16 decodeMS(ADPCMChannelStatus *c, byte);
};
int16 MS_ADPCMStream::decodeMS(ADPCMChannelStatus *c, byte code) {
int32 predictor;
predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 256;
predictor += (signed)((code & 0x08) ? (code - 0x10) : (code)) * c->delta;
predictor = CLIP<int32>(predictor, -32768, 32767);
c->sample2 = c->sample1;
c->sample1 = predictor;
c->delta = (MSADPCMAdaptationTable[(int)code] * c->delta) >> 8;
if (c->delta < 16)
c->delta = 16;
return (int16)predictor;
}
int MS_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
int samples;
byte data;
int i = 0;
samples = 0;
while (samples < numSamples && !_stream->eos() && _stream->pos() < _endpos) {
if (_blockPos[0] == _blockAlign) {
// read block header
for (i = 0; i < _channels; i++) {
_status.ch[i].predictor = CLIP(_stream->readByte(), (byte)0, (byte)6);
_status.ch[i].coeff1 = MSADPCMAdaptCoeff1[_status.ch[i].predictor];
_status.ch[i].coeff2 = MSADPCMAdaptCoeff2[_status.ch[i].predictor];
}
for (i = 0; i < _channels; i++)
_status.ch[i].delta = _stream->readSint16LE();
for (i = 0; i < _channels; i++)
_status.ch[i].sample1 = _stream->readSint16LE();
for (i = 0; i < _channels; i++)
buffer[samples++] = _status.ch[i].sample2 = _stream->readSint16LE();
for (i = 0; i < _channels; i++)
buffer[samples++] = _status.ch[i].sample1;
_blockPos[0] = _channels * 7;
}
for (; samples < numSamples && _blockPos[0] < _blockAlign && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
data = _stream->readByte();
_blockPos[0]++;
buffer[samples] = decodeMS(&_status.ch[0], (data >> 4) & 0x0f);
buffer[samples + 1] = decodeMS(&_status.ch[_channels - 1], data & 0x0f);
}
}
return samples;
}
#pragma mark -
class Tinsel_ADPCMStream : public ADPCMStream {
protected:
struct {
// Tinsel
double predictor;
double K0, K1;
double d0, d1;
} _status;
void reset() {
ADPCMStream::reset();
memset(&_status, 0, sizeof(_status));
}
int16 decodeTinsel(int16, double);
void readBufferTinselHeader();
public:
Tinsel_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
if (blockAlign == 0)
error("Tinsel_ADPCMStream(): blockAlign isn't specified");
if (channels != 1)
error("Tinsel_ADPCMStream(): Tinsel ADPCM only supports mono");
memset(&_status, 0, sizeof(_status));
}
};
static const double TinselFilterTable[4][2] = {
{0, 0 },
{0.9375, 0},
{1.796875, -0.8125},
{1.53125, -0.859375}
};
void Tinsel_ADPCMStream::readBufferTinselHeader() {
uint8 start = _stream->readByte();
uint8 filterVal = (start & 0xC0) >> 6;
if ((start & 0x20) != 0) {
//Lower 6 bit are negative
// Negate
start = ~(start | 0xC0) + 1;
_status.predictor = 1 << start;
} else {
// Lower 6 bit are positive
// Truncate
start &= 0x1F;
_status.predictor = ((double) 1.0) / (1 << start);
}
_status.K0 = TinselFilterTable[filterVal][0];
_status.K1 = TinselFilterTable[filterVal][1];
}
int16 Tinsel_ADPCMStream::decodeTinsel(int16 code, double eVal) {
double sample;
sample = (double) code;
sample *= eVal * _status.predictor;
sample += (_status.d0 * _status.K0) + (_status.d1 * _status.K1);
_status.d1 = _status.d0;
_status.d0 = sample;
return (int16) CLIP<double>(sample, -32768.0, 32767.0);
}
class Tinsel4_ADPCMStream : public Tinsel_ADPCMStream {
public:
Tinsel4_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: Tinsel_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {}
virtual int readBuffer(int16 *buffer, const int numSamples);
};
int Tinsel4_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
int samples;
uint16 data;
const double eVal = 1.142822265;
samples = 0;
assert(numSamples % 2 == 0);
while (samples < numSamples && !_stream->eos() && _stream->pos() < _endpos) {
if (_blockPos[0] == _blockAlign) {
readBufferTinselHeader();
_blockPos[0] = 0;
}
for (; samples < numSamples && _blockPos[0] < _blockAlign && !_stream->eos() && _stream->pos() < _endpos; samples += 2, _blockPos[0]++) {
// Read 1 byte = 8 bits = two 4 bit blocks
data = _stream->readByte();
buffer[samples] = decodeTinsel((data << 8) & 0xF000, eVal);
buffer[samples+1] = decodeTinsel((data << 12) & 0xF000, eVal);
}
}
return samples;
}
class Tinsel6_ADPCMStream : public Tinsel_ADPCMStream {
protected:
uint8 _chunkPos;
uint16 _chunkData;
void reset() {
ADPCMStream::reset();
_chunkPos = 0;
_chunkData = 0;
}
public:
Tinsel6_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: Tinsel_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
_chunkPos = 0;
_chunkData = 0;
}
virtual int readBuffer(int16 *buffer, const int numSamples);
};
int Tinsel6_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
int samples;
const double eVal = 1.032226562;
samples = 0;
while (samples < numSamples && !_stream->eos() && _stream->pos() < _endpos) {
if (_blockPos[0] == _blockAlign) {
readBufferTinselHeader();
_blockPos[0] = 0;
_chunkPos = 0;
}
for (; samples < numSamples && _blockPos[0] < _blockAlign && !_stream->eos() && _stream->pos() < _endpos; samples++, _chunkPos = (_chunkPos + 1) % 4) {
switch (_chunkPos) {
case 0:
_chunkData = _stream->readByte();
buffer[samples] = decodeTinsel((_chunkData << 8) & 0xFC00, eVal);
break;
case 1:
_chunkData = (_chunkData << 8) | (_stream->readByte());
buffer[samples] = decodeTinsel((_chunkData << 6) & 0xFC00, eVal);
_blockPos[0]++;
break;
case 2:
_chunkData = (_chunkData << 8) | (_stream->readByte());
buffer[samples] = decodeTinsel((_chunkData << 4) & 0xFC00, eVal);
_blockPos[0]++;
break;
case 3:
_chunkData = (_chunkData << 8);
buffer[samples] = decodeTinsel((_chunkData << 2) & 0xFC00, eVal);
_blockPos[0]++;
break;
}
}
}
return samples;
}
class Tinsel8_ADPCMStream : public Tinsel_ADPCMStream {
public:
Tinsel8_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: Tinsel_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {}
virtual int readBuffer(int16 *buffer, const int numSamples);
};
int Tinsel8_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
int samples;
byte data;
const double eVal = 1.007843258;
samples = 0;
while (samples < numSamples && !_stream->eos() && _stream->pos() < _endpos) {
if (_blockPos[0] == _blockAlign) {
readBufferTinselHeader();
_blockPos[0] = 0;
}
for (; samples < numSamples && _blockPos[0] < _blockAlign && !_stream->eos() && _stream->pos() < _endpos; samples++, _blockPos[0]++) {
// Read 1 byte = 8 bits = one 8 bit block
data = _stream->readByte();
buffer[samples] = decodeTinsel(data << 8, eVal);
}
}
return samples;
}
#pragma mark -
// adjust the step for use on the next sample.
int16 ADPCMStream::stepAdjust(byte code) {
static const int16 adjusts[] = {-1, -1, -1, -1, 2, 4, 6, 8};
return adjusts[code & 0x07];
}
static const uint16 imaStepTable[89] = {
7, 8, 9, 10, 11, 12, 13, 14,
16, 17, 19, 21, 23, 25, 28, 31,
34, 37, 41, 45, 50, 55, 60, 66,
73, 80, 88, 97, 107, 118, 130, 143,
157, 173, 190, 209, 230, 253, 279, 307,
337, 371, 408, 449, 494, 544, 598, 658,
724, 796, 876, 963, 1060, 1166, 1282, 1411,
1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024,
3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484,
7132, 7845, 8630, 9493,10442,11487,12635,13899,
15289,16818,18500,20350,22385,24623,27086,29794,
32767
};
int16 Ima_ADPCMStream::decodeIMA(byte code, int channel) {
int32 E = (2 * (code & 0x7) + 1) * imaStepTable[_status.ima_ch[channel].stepIndex] / 8;
int32 diff = (code & 0x08) ? -E : E;
int32 samp = CLIP<int32>(_status.ima_ch[channel].last + diff, -32768, 32767);
_status.ima_ch[channel].last = samp;
_status.ima_ch[channel].stepIndex += stepAdjust(code);
_status.ima_ch[channel].stepIndex = CLIP<int32>(_status.ima_ch[channel].stepIndex, 0, ARRAYSIZE(imaStepTable) - 1);
return samp;
}
RewindableAudioStream *makeADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, typesADPCM type, int rate, int channels, uint32 blockAlign) {
// If size is 0, report the entire size of the stream
if (!size)
size = stream->size();
switch (type) {
case kADPCMOki:
return new Oki_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign);
case kADPCMMSIma:
return new MSIma_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign);
case kADPCMMSImaLastExpress:
return new MSIma_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign, true);
case kADPCMMS:
return new MS_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign);
case kADPCMTinsel4:
return new Tinsel4_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign);
case kADPCMTinsel6:
return new Tinsel6_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign);
case kADPCMTinsel8:
return new Tinsel8_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign);
case kADPCMIma:
return new Ima_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign);
case kADPCMApple:
return new Apple_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign);
default:
error("Unsupported ADPCM encoding");
break;
}
}
} // End of namespace Audio
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