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-rw-r--r--sound/adpcm.cpp144
1 files changed, 125 insertions, 19 deletions
diff --git a/sound/adpcm.cpp b/sound/adpcm.cpp
index d523bf84bc..d2e1e72aed 100644
--- a/sound/adpcm.cpp
+++ b/sound/adpcm.cpp
@@ -38,46 +38,67 @@ private:
int _channels;
typesADPCM _type;
uint32 _blockAlign;
+ uint32 _blockPos;
+ int _blockLen;
+ int _rate;
+
+ struct ADPCMChannelStatus {
+ byte predictor;
+ int16 delta;
+ int16 coeff1;
+ int16 coeff2;
+ int16 sample1;
+ int16 sample2;
+ };
struct adpcmStatus {
+ // IMA
int32 last;
int32 stepIndex;
+
+ // MS ADPCM
+ ADPCMChannelStatus ch[2];
} _status;
int16 stepAdjust(byte);
int16 decodeOKI(byte);
int16 decodeMSIMA(byte);
+ int16 decodeMS(ADPCMChannelStatus *c, byte);
public:
- ADPCMInputStream(Common::SeekableReadStream *stream, uint32 size, typesADPCM type, int channels = 2, uint32 blockAlign = 0);
+ ADPCMInputStream(Common::SeekableReadStream *stream, uint32 size, typesADPCM type, int rate, int channels = 2, uint32 blockAlign = 0);
~ADPCMInputStream() {};
int readBuffer(int16 *buffer, const int numSamples);
int readBufferOKI(int16 *buffer, const int numSamples);
int readBufferMSIMA1(int16 *buffer, const int numSamples);
int readBufferMSIMA2(int16 *buffer, const int numSamples);
+ int readBufferMS(int channels, int16 *buffer, const int numSamples);
bool endOfData() const { return (_stream->eos() || _stream->pos() >= _endpos); }
bool isStereo() const { return false; }
- int getRate() const { return 22050; }
+ int getRate() const { return _rate; }
};
// 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>
//
-// In addition, also IMA ADPCM is supported. See
-// <http://www.multimedia.cx/simpleaudio.html>.
+// In addition, also MS IMA ADPCM is supported. See
+// <http://wiki.multimedia.cx/index.php?title=Microsoft_IMA_ADPCM>.
-ADPCMInputStream::ADPCMInputStream(Common::SeekableReadStream *stream, uint32 size, typesADPCM type, int channels, uint32 blockAlign)
- : _stream(stream), _channels(channels), _type(type), _blockAlign(blockAlign) {
+ADPCMInputStream::ADPCMInputStream(Common::SeekableReadStream *stream, uint32 size, typesADPCM type, int rate, int channels, uint32 blockAlign)
+ : _stream(stream), _channels(channels), _type(type), _blockAlign(blockAlign), _rate(rate) {
_status.last = 0;
_status.stepIndex = 0;
_endpos = stream->pos() + size;
+ _blockPos = _blockLen = 0;
- if (type == kADPCMIma && blockAlign == 0)
- error("ADPCMInputStream(): blockAlign isn't specifiled for MS ADPCM IMA");
+ if (type == kADPCMMSIma && blockAlign == 0)
+ error("ADPCMInputStream(): blockAlign isn't specifiled for MS IMA ADPCM");
+ if (type == kADPCMMS && blockAlign == 0)
+ error("ADPCMInputStream(): blockAlign isn't specifiled for MS ADPCM");
}
int ADPCMInputStream::readBuffer(int16 *buffer, const int numSamples) {
@@ -85,12 +106,15 @@ int ADPCMInputStream::readBuffer(int16 *buffer, const int numSamples) {
case kADPCMOki:
return readBufferOKI(buffer, numSamples);
break;
- case kADPCMIma:
+ case kADPCMMSIma:
if (_channels == 1)
return readBufferMSIMA1(buffer, numSamples);
else
return readBufferMSIMA2(buffer, numSamples);
break;
+ case kADPCMMS:
+ return readBufferMS(_channels, buffer, numSamples);
+ break;
default:
error("Unsupported ADPCM encoding");
break;
@@ -116,22 +140,22 @@ int ADPCMInputStream::readBufferOKI(int16 *buffer, const int numSamples) {
int ADPCMInputStream::readBufferMSIMA1(int16 *buffer, const int numSamples) {
int samples;
byte data;
- int blockLen;
- int i;
assert(numSamples % 2 == 0);
samples = 0;
while (samples < numSamples && !_stream->eos() && _stream->pos() < _endpos) {
- // read block header
- _status.last = _stream->readSint16LE();
- _status.stepIndex = _stream->readSint16LE();
-
- blockLen = MIN(_endpos - _stream->pos(), _blockAlign - 4);
+ if (_blockPos == _blockAlign) {
+ // read block header
+ _status.last = _stream->readSint16LE();
+ _status.stepIndex = _stream->readSint16LE();
+ _blockPos = 4;
+ }
- for (i = 0; i < blockLen && !_stream->eos() && _stream->pos() < _endpos; i++, samples += 2) {
+ for (; samples < numSamples && _blockPos < _blockAlign && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
data = _stream->readByte();
+ _blockPos++;
buffer[samples] = TO_LE_16(decodeMSIMA(data & 0x0f));
buffer[samples + 1] = TO_LE_16(decodeMSIMA((data >> 4) & 0x0f));
}
@@ -162,6 +186,61 @@ int ADPCMInputStream::readBufferMSIMA2(int16 *buffer, const int numSamples) {
return samples;
}
+static const int MSADPCMAdaptCoeff1[] = {
+ 256, 512, 0, 192, 240, 460, 392
+};
+
+static const int MSADPCMAdaptCoeff2[] = {
+ 0, -256, 0, 64, 0, -208, -232
+};
+
+int ADPCMInputStream::readBufferMS(int channels, int16 *buffer, const int numSamples) {
+ int samples;
+ byte data;
+ int stereo = channels - 1; // We use it in index
+
+ samples = 0;
+
+ while (samples < numSamples && !_stream->eos() && _stream->pos() < _endpos) {
+ if (_blockPos == _blockAlign) {
+ // read block header
+ _status.ch[0].predictor = CLIP(_stream->readByte(), (byte)0, (byte)6);
+ _status.ch[0].coeff1 = MSADPCMAdaptCoeff1[_status.ch[0].predictor];
+ _status.ch[0].coeff2 = MSADPCMAdaptCoeff2[_status.ch[0].predictor];
+ if (stereo) {
+ _status.ch[1].predictor = CLIP(_stream->readByte(), (byte)0, (byte)6);
+ _status.ch[1].coeff1 = MSADPCMAdaptCoeff1[_status.ch[1].predictor];
+ _status.ch[1].coeff2 = MSADPCMAdaptCoeff2[_status.ch[1].predictor];
+ }
+
+ _status.ch[0].delta = _stream->readSint16LE();
+ if (stereo)
+ _status.ch[1].delta = _stream->readSint16LE();
+
+ buffer[samples++] = _status.ch[0].sample1 = _stream->readSint16LE();
+ if (stereo)
+ buffer[samples++] = _status.ch[1].sample1 = _stream->readSint16LE();
+
+ buffer[samples++] = _status.ch[0].sample2 = _stream->readSint16LE();
+ if (stereo)
+ buffer[samples++] = _status.ch[1].sample2 = _stream->readSint16LE();
+
+ _blockPos = channels * 7;
+ }
+
+
+ for (; samples < numSamples && _blockPos < _blockAlign && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
+ data = _stream->readByte();
+ _blockPos++;
+ buffer[samples] = TO_LE_16(decodeMS(&_status.ch[0], (data >> 4) & 0x0f));
+ buffer[samples + 1] = TO_LE_16(decodeMS(&_status.ch[stereo], data & 0x0f));
+ }
+ }
+
+ return samples;
+}
+
+
// adjust the step for use on the next sample.
int16 ADPCMInputStream::stepAdjust(byte code) {
static const int16 adjusts[] = {-1, -1, -1, -1, 2, 4, 6, 8};
@@ -243,6 +322,33 @@ int16 ADPCMInputStream::decodeMSIMA(byte code) {
return samp;
}
-AudioStream *makeADPCMStream(Common::SeekableReadStream *stream, uint32 size, typesADPCM type, int channels, uint32 blockAlign) {
- return new ADPCMInputStream(stream, size, type, channels, blockAlign);
+static const int MSADPCMAdaptationTable[] = {
+ 230, 230, 230, 230, 307, 409, 512, 614,
+ 768, 614, 512, 409, 307, 230, 230, 230
+};
+
+
+int16 ADPCMInputStream::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;
+
+ if (predictor < -0x8000)
+ predictor = -0x8000;
+ else if (predictor > 0x7fff)
+ predictor = 0x7fff;
+
+ 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;
+}
+
+AudioStream *makeADPCMStream(Common::SeekableReadStream *stream, uint32 size, typesADPCM type, int rate, int channels, uint32 blockAlign) {
+ return new ADPCMInputStream(stream, size, type, rate, channels, blockAlign);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-21 21:09:31 +0000