mirror of
https://github.com/libretro/scummvm.git
synced 2024-12-14 13:50:13 +00:00
138 lines
3.3 KiB
C++
138 lines
3.3 KiB
C++
/* 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 "common/util.h"
|
|
|
|
#include "made/sound.h"
|
|
|
|
namespace Made {
|
|
|
|
void decompressSound(byte *source, byte *dest, uint16 chunkSize, uint16 chunkCount) {
|
|
|
|
int16 prevSample = 0, workSample = 0;
|
|
byte soundBuffer[1025];
|
|
byte deltaSoundBuffer[1024];
|
|
int16 soundBuffer2[16];
|
|
byte deltaType, type;
|
|
uint16 workChunkSize, byteCount, bitCount;
|
|
byte bitMask, bitShift;
|
|
uint16 ofs = 0;
|
|
uint16 i = 0, l = 0;
|
|
byte val;
|
|
|
|
const int modeValues[3][4] = {
|
|
{ 2, 8, 0x01, 1},
|
|
{ 4, 4, 0x03, 2},
|
|
{16, 2, 0x0F, 4}
|
|
};
|
|
|
|
while (chunkCount--) {
|
|
deltaType = (*source) >> 6;
|
|
workChunkSize = chunkSize;
|
|
|
|
if (deltaType == 1)
|
|
workChunkSize /= 2;
|
|
else if (deltaType == 2)
|
|
workChunkSize /= 4;
|
|
|
|
type = (*source++) & 0x0F;
|
|
|
|
workSample = prevSample;
|
|
|
|
switch (type) {
|
|
|
|
case 0:
|
|
memset(soundBuffer, 0x80, workChunkSize);
|
|
workSample = 0;
|
|
break;
|
|
|
|
case 1:
|
|
break;
|
|
|
|
case 2:
|
|
case 3:
|
|
case 4:
|
|
byteCount = modeValues[type - 2][0];
|
|
bitCount = modeValues[type - 2][1];
|
|
bitMask = modeValues[type - 2][2];
|
|
bitShift = modeValues[type - 2][3];
|
|
ofs = 0;
|
|
|
|
for (i = 0; i < byteCount; i++)
|
|
soundBuffer2[i] = (*source++) * 2 - 128;
|
|
|
|
while (ofs < workChunkSize) {
|
|
val = *source++;
|
|
for (i = 0; i < bitCount; i++) {
|
|
workSample = CLIP<int16>(workSample + soundBuffer2[val & bitMask], -127, 127);
|
|
val >>= bitShift;
|
|
soundBuffer[ofs++] = workSample + 128;
|
|
}
|
|
}
|
|
|
|
break;
|
|
|
|
case 5:
|
|
for (i = 0; i < workChunkSize; i++)
|
|
soundBuffer[i] = *source++;
|
|
workSample = soundBuffer[workChunkSize - 1] - 128;
|
|
break;
|
|
|
|
default:
|
|
return;
|
|
|
|
}
|
|
|
|
if (deltaType > 0) {
|
|
if (deltaType == 1) {
|
|
for (i = 0; i < chunkSize - 1; i += 2) {
|
|
l = i / 2;
|
|
deltaSoundBuffer[i] = soundBuffer[l];
|
|
deltaSoundBuffer[i + 1] = (soundBuffer[l] + soundBuffer[l + 1]) / 2;
|
|
}
|
|
} else if (deltaType == 2) {
|
|
for (i = 0; i < chunkSize - 1; i += 4) {
|
|
l = i / 4;
|
|
deltaSoundBuffer[i] = soundBuffer[l];
|
|
deltaSoundBuffer[i + 2] = (soundBuffer[l] + soundBuffer[l + 1]) / 2;
|
|
deltaSoundBuffer[i + 1] = (deltaSoundBuffer[i + 2] + soundBuffer[l]) / 2;
|
|
deltaSoundBuffer[i + 3] = (deltaSoundBuffer[i + 2] + soundBuffer[l + 1]) / 2;
|
|
}
|
|
}
|
|
for (i = 0; i < chunkSize; i++)
|
|
soundBuffer[i] = deltaSoundBuffer[i];
|
|
}
|
|
|
|
prevSample = workSample;
|
|
memcpy(dest, soundBuffer, chunkSize);
|
|
dest += chunkSize;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
} // End of namespace Made
|