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Fix bug #1501302: "FF: Crackling Audio (Mac version)"

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svn-id: r23970
This commit is contained in:
Eugene Sandulenko
2006-09-21 20:12:16 +00:00
parent a857bdeca3
commit 4e8df88c81
1 changed files with 36 additions and 31 deletions
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sound/adpcm.cpp
+36 -31
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@@ -96,7 +96,8 @@ ADPCMInputStream::ADPCMInputStream(Common::SeekableReadStream *stream, uint32 si
_status.stepIndex = 0;
memset(_status.ch, 0, sizeof(_status.ch));
_endpos = stream->pos() + size;
_blockPos = _blockLen = 0;
_blockLen = 0;
_blockPos = _blockAlign; // To make sure first header is read
if (type == kADPCMMSIma && blockAlign == 0)
error("ADPCMInputStream(): blockAlign isn't specifiled for MS IMA ADPCM");
@@ -217,18 +218,22 @@ int ADPCMInputStream::readBufferMS(int channels, int16 *buffer, const int numSam
if (stereo)
_status.ch[1].delta = _stream->readSint16LE();
buffer[samples++] = _status.ch[0].sample1 = _stream->readSint16LE();
_status.ch[0].sample1 = _stream->readSint16LE();
if (stereo)
buffer[samples++] = _status.ch[1].sample1 = _stream->readSint16LE();
_status.ch[1].sample1 = _stream->readSint16LE();
buffer[samples++] = _status.ch[0].sample2 = _stream->readSint16LE();
if (stereo)
buffer[samples++] = _status.ch[1].sample2 = _stream->readSint16LE();
buffer[samples++] = _status.ch[0].sample1;
if (stereo)
buffer[samples++] = _status.ch[1].sample1;
_blockPos = channels * 7;
}
for (; samples < numSamples && _blockPos < _blockAlign && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
data = _stream->readByte();
_blockPos++;
@@ -241,6 +246,33 @@ int ADPCMInputStream::readBufferMS(int channels, int16 *buffer, const int numSam
}
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;
}
// 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};
@@ -322,33 +354,6 @@ int16 ADPCMInputStream::decodeMSIMA(byte code) {
return samp;
}
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);
}