diff options
Diffstat (limited to 'scumm/imuse_digi/dimuse_codecs.cpp')
| -rw-r--r-- | scumm/imuse_digi/dimuse_codecs.cpp | 32 |
1 files changed, 16 insertions, 16 deletions
diff --git a/scumm/imuse_digi/dimuse_codecs.cpp b/scumm/imuse_digi/dimuse_codecs.cpp index 40e3616b04..46dd0c6720 100644 --- a/scumm/imuse_digi/dimuse_codecs.cpp +++ b/scumm/imuse_digi/dimuse_codecs.cpp @@ -48,7 +48,7 @@ uint32 decode12BitsSample(const byte *src, byte **dst, uint32 size) { * The "IMC" codec below (see cases 13 & 15 in decompressCodec) is actually a * variant of the IMA codec, see also * <http://home.pcisys.net/~melanson/codecs/simpleaudio.html> - * + * * It is somewhat different, though: the standard ADPCM codecs use a fixed * size for their data packets (4 bits), while the codec implemented here * varies the size of each "packet" between 2 and 7 bits. @@ -80,27 +80,27 @@ static const byte imxOtherTable[6][64] = { { 0xFF, 0x04 }, - + { 0xFF, 0xFF, 0x02, 0x08 }, - + { 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0x02, 0x04, 0x06 }, - + { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0x02, 0x04, 0x06, 0x08, 0x0C, 0x10, 0x20 }, - + { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0x02, 0x04, 0x06, 0x08, 0x0A, 0x0C, 0x0E, 0x10, 0x12, 0x14, 0x16, 0x18, 0x1A, 0x1C, 0x20 }, - + { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, @@ -122,12 +122,12 @@ void releaseImcTables() { void initializeImcTables() { int pos; - + #ifdef __PALM_OS__ if (!_destImcTable) _destImcTable = (byte *)calloc(89, sizeof(byte)); if (!_destImcTable2) _destImcTable2 = (uint32 *)calloc(89 * 64, sizeof(uint32)); #endif - + for (pos = 0; pos <= 88; ++pos) { byte put = 1; int32 tableValue = ((imcTable[pos] * 4) / 7) / 2; @@ -537,7 +537,7 @@ int32 decompressCodec(int32 codec, byte *comp_input, byte *comp_output, int32 in // Decoder for the the IMA ADPCM variants used in COMI. // Contrary to regular IMA ADPCM, this codec uses a variable // bitsize for the encoded data. - + const int MAX_CHANNELS = 2; int32 outputSamplesLeft; int32 destPos; @@ -558,7 +558,7 @@ int32 decompressCodec(int32 codec, byte *comp_input, byte *comp_output, int32 in outputSamplesLeft = 0x1000; // Every data packet contains 0x2000 bytes of audio data - // when extracted. In order to encode bigger data sets, + // when extracted. In order to encode bigger data sets, // one has to split the data into multiple blocks. // // Every block starts with a 2 byte word. If that word is @@ -604,7 +604,7 @@ int32 decompressCodec(int32 codec, byte *comp_input, byte *comp_output, int32 in destPos = chan * 2; const int bound = (channels == 1) - ? outputSamplesLeft + ? outputSamplesLeft : ((chan == 0) ? (outputSamplesLeft+1) / 2 : outputSamplesLeft / 2); @@ -612,7 +612,7 @@ int32 decompressCodec(int32 codec, byte *comp_input, byte *comp_output, int32 in // Determine the size (in bits) of the next data packet const int32 curTableEntryBitCount = _destImcTable[curTablePos]; assert(2 <= curTableEntryBitCount && curTableEntryBitCount <= 7); - + // Read the next data packet const byte *readPos = src + (totalBitOffset >> 3); const uint16 readWord = (uint16)(READ_BE_UINT16(readPos) << (totalBitOffset & 7)); @@ -620,7 +620,7 @@ int32 decompressCodec(int32 codec, byte *comp_input, byte *comp_output, int32 in // Advance read position to the next data packet totalBitOffset += curTableEntryBitCount; - + // Decode the data packet into a delta value for the output signal. const byte signBitMask = (1 << (curTableEntryBitCount - 1)); const byte dataBitMask = (signBitMask - 1); @@ -629,13 +629,13 @@ int32 decompressCodec(int32 codec, byte *comp_input, byte *comp_output, int32 in const int32 tmpA = (data << (7 - curTableEntryBitCount)); const int32 imcTableEntry = imcTable[curTablePos] >> (curTableEntryBitCount - 1); int32 delta = imcTableEntry + _destImcTable2[tmpA + (curTablePos * 64)]; - + // The topmost bit in the data packet tells is a sign bit if ((packet & signBitMask) != 0) { delta = -delta; } - - // Accumulate the delta onto the output data + + // Accumulate the delta onto the output data outputWord += delta; // Clip outputWord to 16 bit signed, and write it into the destination stream |