[Scummvm-cvs-logs] SF.net SVN: scummvm:[47739] scummvm/trunk/sound/decoders/adpcm.cpp
fingolfin at users.sourceforge.net
fingolfin at users.sourceforge.net
Sun Jan 31 03:13:38 CET 2010
Revision: 47739
http://scummvm.svn.sourceforge.net/scummvm/?rev=47739&view=rev
Author: fingolfin
Date: 2010-01-31 02:13:38 +0000 (Sun, 31 Jan 2010)
Log Message:
-----------
Rearrange code of ADPCMStream subclasses
Modified Paths:
--------------
scummvm/trunk/sound/decoders/adpcm.cpp
Modified: scummvm/trunk/sound/decoders/adpcm.cpp
===================================================================
--- scummvm/trunk/sound/decoders/adpcm.cpp 2010-01-31 02:12:59 UTC (rev 47738)
+++ scummvm/trunk/sound/decoders/adpcm.cpp 2010-01-31 02:13:38 UTC (rev 47739)
@@ -54,7 +54,7 @@
int16 sample2;
};
- struct adpcmStatus {
+ struct {
// OKI/IMA
struct {
int32 last;
@@ -160,6 +160,35 @@
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 @@
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 @@
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 @@
}
+
#pragma mark -
@@ -464,6 +518,19 @@
_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 @@
#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 @@
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 @@
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:
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