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Rearrange code of ADPCMStream subclasses

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svn-id: r47739
This commit is contained in:
Max Horn 2010-01-31 02:13:38 +00:00
parent f3322bb1c8
commit 7f2f9a8117
1 changed files with 68 additions and 66 deletions
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134
sound/decoders/adpcm.cpp
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@ -54,7 +54,7 @@ protected:
int16 sample2;
};
struct adpcmStatus {
struct {
// OKI/IMA
struct {
int32 last;
@ -160,6 +160,35 @@ int Oki_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
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 -
@ -355,6 +384,12 @@ 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 {
public:
MS_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
@ -369,6 +404,24 @@ 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;
@ -412,6 +465,7 @@ int MS_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
}
#pragma mark -
@ -464,6 +518,19 @@ void Tinsel_ADPCMStream::readBufferTinselHeader() {
_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)
@ -585,30 +652,6 @@ int Tinsel8_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
#pragma mark -
static const int MSADPCMAdaptationTable[] = {
230, 230, 230, 230, 307, 409, 512, 614,
768, 614, 512, 409, 307, 230, 230, 230
};
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;
}
// 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};
@ -616,34 +659,6 @@ int16 ADPCMStream::stepAdjust(byte code) {
return adjusts[code & 0x07];
}
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;
}
static const uint16 imaStepTable[89] = {
7, 8, 9, 10, 11, 12, 13, 14,
16, 17, 19, 21, 23, 25, 28, 31,
@ -671,19 +686,6 @@ int16 ADPCMStream::decodeIMA(byte code, int channel) {
return samp;
}
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);
}
RewindableAudioStream *makeADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, typesADPCM type, int rate, int channels, uint32 blockAlign) {
switch (type) {
case kADPCMOki: