mirror of
https://github.com/vgmstream/vgmstream.git
synced 2024-12-21 02:45:52 +01:00
bf8a32fefd
git-svn-id: https://vgmstream.svn.sourceforge.net/svnroot/vgmstream@913 51a99a44-fe44-0410-b1ba-c3e57ba2b86b
638 lines
21 KiB
C
638 lines
21 KiB
C
#include "../util.h"
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#include "coding.h"
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const int32_t ADPCMTable[89] =
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{
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7, 8, 9, 10, 11, 12, 13, 14,
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16, 17, 19, 21, 23, 25, 28, 31,
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34, 37, 41, 45, 50, 55, 60, 66,
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73, 80, 88, 97, 107, 118, 130, 143,
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157, 173, 190, 209, 230, 253, 279, 307,
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337, 371, 408, 449, 494, 544, 598, 658,
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724, 796, 876, 963, 1060, 1166, 1282, 1411,
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1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024,
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3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484,
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7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
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15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794,
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32767
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};
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const int IMA_IndexTable[16] =
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{
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-1, -1, -1, -1, 2, 4, 6, 8,
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-1, -1, -1, -1, 2, 4, 6, 8
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};
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void decode_nds_ima(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do) {
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int i=first_sample;
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int32_t sample_count;
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int32_t hist1 = stream->adpcm_history1_16;
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int step_index = stream->adpcm_step_index;
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if (first_sample==0) {
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hist1 = read_16bitLE(stream->offset,stream->streamfile);
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step_index = read_16bitLE(stream->offset+2,stream->streamfile);
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}
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for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
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int sample_nibble =
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(read_8bit(stream->offset+4+i/2,stream->streamfile) >> (i&1?4:0))&0xf;
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int delta;
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int step = ADPCMTable[step_index];
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delta = step >> 3;
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if (sample_nibble & 1) delta += step >> 2;
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if (sample_nibble & 2) delta += step >> 1;
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if (sample_nibble & 4) delta += step;
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if (sample_nibble & 8)
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outbuf[sample_count] = clamp16(hist1 - delta);
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else
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outbuf[sample_count] = clamp16(hist1 + delta);
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step_index += IMA_IndexTable[sample_nibble];
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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hist1 = outbuf[sample_count];
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}
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stream->adpcm_history1_16 = hist1;
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stream->adpcm_step_index = step_index;
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}
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void decode_dat4_ima(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do) {
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int i=first_sample;
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int32_t sample_count;
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int32_t hist1 = stream->adpcm_history1_16;
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int step_index = stream->adpcm_step_index;
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if (first_sample==0) {
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hist1 = read_16bitLE(stream->offset,stream->streamfile);
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step_index = read_8bit(stream->offset+2,stream->streamfile);
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}
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for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
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int sample_nibble =
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(read_8bit(stream->offset+4+i/2,stream->streamfile) >> (i&1?0:4))&0xf;
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int delta;
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int step = ADPCMTable[step_index];
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delta = step >> 3;
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if (sample_nibble & 1) delta += step >> 2;
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if (sample_nibble & 2) delta += step >> 1;
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if (sample_nibble & 4) delta += step;
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if (sample_nibble & 8)
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outbuf[sample_count] = clamp16(hist1 - delta);
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else
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outbuf[sample_count] = clamp16(hist1 + delta);
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step_index += IMA_IndexTable[sample_nibble];
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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hist1 = outbuf[sample_count];
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}
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stream->adpcm_history1_16 = hist1;
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stream->adpcm_step_index = step_index;
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}
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/* Xbox IMA is MS IMA, but I'll leave it alone for now (esp as it has > 2 channel support) */
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void decode_ms_ima(VGMSTREAM * vgmstream,VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do,int channel) {
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int i=first_sample;
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int sample_nibble;
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int sample_decoded;
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int delta;
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int block_samples = (vgmstream->interleave_block_size - vgmstream->channels * 4) * 2 / vgmstream->channels;
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int32_t sample_count=0;
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int32_t hist1=stream->adpcm_history1_32;
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int step_index = stream->adpcm_step_index;
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off_t offset=stream->offset;
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first_sample = first_sample % block_samples;
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if (first_sample == 0) {
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hist1 = read_16bitLE(offset+channel*4,stream->streamfile);
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step_index = read_16bitLE(offset+channel*4+2,stream->streamfile);
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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}
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for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
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int step = ADPCMTable[step_index];
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offset = stream->offset + 4*vgmstream->channels + (i/8*4*vgmstream->channels) + (i%8)/2 + 4*channel;
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sample_nibble = (read_8bit(offset,stream->streamfile) >> (i&1?4:0))&0xf;
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sample_decoded=hist1;
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delta = step >> 3;
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if (sample_nibble & 1) delta += step >> 2;
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if (sample_nibble & 2) delta += step >> 1;
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if (sample_nibble & 4) delta += step;
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if (sample_nibble & 8)
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sample_decoded -= delta;
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else
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sample_decoded += delta;
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hist1=clamp16(sample_decoded);
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step_index += IMA_IndexTable[sample_nibble];
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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outbuf[sample_count]=(short)(hist1);
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}
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// Only increment offset on complete frame
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if (i == block_samples) stream->offset += vgmstream->interleave_block_size;
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stream->adpcm_history1_32=hist1;
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stream->adpcm_step_index=step_index;
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}
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// "Radical ADPCM", essentially MS IMA
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void decode_rad_ima(VGMSTREAM * vgmstream,VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do,int channel) {
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int i=first_sample;
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int sample_nibble;
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int sample_decoded;
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int delta;
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int block_samples = (vgmstream->interleave_block_size - vgmstream->channels * 4) * 2 / vgmstream->channels;
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int32_t sample_count=0;
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int32_t hist1=stream->adpcm_history1_32;
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int step_index = stream->adpcm_step_index;
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off_t offset=stream->offset;
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first_sample = first_sample % block_samples;
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if (first_sample == 0) {
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hist1 = read_16bitLE(offset+channel*4+2,stream->streamfile);
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step_index = read_16bitLE(offset+channel*4,stream->streamfile);
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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}
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for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
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int step = ADPCMTable[step_index];
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offset = stream->offset + 4*vgmstream->channels + (i/2*vgmstream->channels) + channel;
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sample_nibble = (read_8bit(offset,stream->streamfile) >> (i&1?4:0))&0xf;
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sample_decoded=hist1;
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delta = step >> 3;
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if (sample_nibble & 1) delta += step >> 2;
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if (sample_nibble & 2) delta += step >> 1;
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if (sample_nibble & 4) delta += step;
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if (sample_nibble & 8)
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sample_decoded -= delta;
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else
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sample_decoded += delta;
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hist1=clamp16(sample_decoded);
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step_index += IMA_IndexTable[sample_nibble];
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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outbuf[sample_count]=(short)(hist1);
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}
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// Only increment offset on complete frame
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if (i == block_samples) stream->offset += vgmstream->interleave_block_size;
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stream->adpcm_history1_32=hist1;
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stream->adpcm_step_index=step_index;
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}
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// "Radical ADPCM", mono form (for use with interleave layout)
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// I think this is exactly equivalent to mono MS APDCM, but I need a
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// channel-agnostic version to use within an interleave.
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void decode_rad_ima_mono(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do) {
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int i=first_sample;
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int sample_nibble;
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int sample_decoded;
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int delta;
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int block_samples = 0x14 * 2;
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int32_t sample_count=0;
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int32_t hist1=stream->adpcm_history1_32;
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int step_index = stream->adpcm_step_index;
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off_t offset=stream->offset;
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first_sample = first_sample % block_samples;
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if (first_sample == 0) {
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hist1 = read_16bitLE(offset+2,stream->streamfile);
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step_index = read_16bitLE(offset,stream->streamfile);
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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}
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for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
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int step = ADPCMTable[step_index];
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offset = stream->offset + 4 + (i/2);
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sample_nibble = (read_8bit(offset,stream->streamfile) >> (i&1?4:0))&0xf;
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sample_decoded=hist1;
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delta = step >> 3;
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if (sample_nibble & 1) delta += step >> 2;
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if (sample_nibble & 2) delta += step >> 1;
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if (sample_nibble & 4) delta += step;
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if (sample_nibble & 8)
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sample_decoded -= delta;
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else
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sample_decoded += delta;
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hist1=clamp16(sample_decoded);
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step_index += IMA_IndexTable[sample_nibble];
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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outbuf[sample_count]=(short)(hist1);
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}
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stream->adpcm_history1_32=hist1;
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stream->adpcm_step_index=step_index;
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}
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void decode_xbox_ima(VGMSTREAM * vgmstream,VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do,int channel) {
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int i=first_sample;
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int sample_nibble;
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int sample_decoded;
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int delta;
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int32_t sample_count=0;
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int32_t hist1=stream->adpcm_history1_32;
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int step_index = stream->adpcm_step_index;
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off_t offset=stream->offset;
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if(vgmstream->channels==1)
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first_sample = first_sample % 32;
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else
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first_sample = first_sample % (32*(vgmstream->channels&2));
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if (first_sample == 0) {
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if(vgmstream->layout_type==layout_ea_blocked) {
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hist1 = read_16bitLE(offset,stream->streamfile);
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step_index = read_16bitLE(offset+2,stream->streamfile);
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} else {
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hist1 = read_16bitLE(offset+(channel%2)*4,stream->streamfile);
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step_index = read_16bitLE(offset+(channel%2)*4+2,stream->streamfile);
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}
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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}
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for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
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int step = ADPCMTable[step_index];
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if(vgmstream->layout_type==layout_ea_blocked)
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offset = stream->offset + (i/8*4+(i%8)/2+4);
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else {
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if(channelspacing==1)
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offset = stream->offset + 4 + (i/8*4+(i%8)/2+4*(channel%2));
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else
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offset = stream->offset + 4*2 + (i/8*4*2+(i%8)/2+4*(channel%2));
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}
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sample_nibble = (read_8bit(offset,stream->streamfile) >> (i&1?4:0))&0xf;
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sample_decoded=hist1;
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delta = step >> 3;
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if (sample_nibble & 1) delta += step >> 2;
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if (sample_nibble & 2) delta += step >> 1;
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if (sample_nibble & 4) delta += step;
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if (sample_nibble & 8)
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sample_decoded -= delta;
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else
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sample_decoded += delta;
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hist1=clamp16(sample_decoded);
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step_index += IMA_IndexTable[sample_nibble];
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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outbuf[sample_count]=(short)(hist1);
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}
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// Only increment offset on complete frame
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if(vgmstream->layout_type==layout_ea_blocked) {
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if(offset-stream->offset==32+3) // ??
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stream->offset+=36;
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} else {
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if(channelspacing==1) {
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if(offset-stream->offset==32+3) // ??
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stream->offset+=36;
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} else {
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if(offset-stream->offset==64+(4*(channel%2))+3) // ??
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stream->offset+=36*channelspacing;
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}
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}
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stream->adpcm_history1_32=hist1;
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stream->adpcm_step_index=step_index;
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}
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void decode_int_xbox_ima(VGMSTREAM * vgmstream,VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do,int channel) {
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int i=first_sample;
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int sample_nibble;
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int sample_decoded;
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int delta;
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int32_t sample_count=0;
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int32_t hist1=stream->adpcm_history1_32;
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int step_index = stream->adpcm_step_index;
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off_t offset=stream->offset;
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if(vgmstream->channels==1)
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first_sample = first_sample % 32;
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else
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first_sample = first_sample % (32*(vgmstream->channels&2));
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if (first_sample == 0) {
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hist1 = read_16bitLE(offset,stream->streamfile);
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step_index = read_16bitLE(offset+2,stream->streamfile);
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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}
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for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
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int step = ADPCMTable[step_index];
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offset = stream->offset + 4 + (i/8*4+(i%8)/2);
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sample_nibble = (read_8bit(offset,stream->streamfile) >> (i&1?4:0))&0xf;
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sample_decoded=hist1;
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delta = step >> 3;
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if (sample_nibble & 1) delta += step >> 2;
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if (sample_nibble & 2) delta += step >> 1;
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if (sample_nibble & 4) delta += step;
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if (sample_nibble & 8)
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sample_decoded -= delta;
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else
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sample_decoded += delta;
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hist1=clamp16(sample_decoded);
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step_index += IMA_IndexTable[sample_nibble];
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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outbuf[sample_count]=(short)(hist1);
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}
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// Only increment offset on complete frame
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if(channelspacing==1) {
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if(offset-stream->offset==32+3) // ??
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stream->offset+=36;
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} else {
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if(offset-stream->offset==64+(4*(channel%2))+3) // ??
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stream->offset+=36*channelspacing;
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}
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stream->adpcm_history1_32=hist1;
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stream->adpcm_step_index=step_index;
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}
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void decode_dvi_ima(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do) {
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int i;
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int32_t sample_count=0;
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int32_t hist1=stream->adpcm_history1_32;
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int step_index = stream->adpcm_step_index;
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for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
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int step = ADPCMTable[step_index];
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uint8_t sample_byte;
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int sample_nibble;
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int sample_decoded;
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int delta;
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sample_byte = read_8bit(stream->offset+i/2,stream->streamfile);
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/* old-style DVI takes high nibble first */
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sample_nibble = (sample_byte >> (i&1?0:4))&0xf;
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sample_decoded = hist1;
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delta = step >> 3;
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if (sample_nibble & 1) delta += step >> 2;
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if (sample_nibble & 2) delta += step >> 1;
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if (sample_nibble & 4) delta += step;
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if (sample_nibble & 8)
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sample_decoded -= delta;
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else
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sample_decoded += delta;
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hist1=clamp16(sample_decoded);
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step_index += IMA_IndexTable[sample_nibble&0x7];
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if (step_index < 0) step_index=0;
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if (step_index > 88) step_index=88;
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outbuf[sample_count]=(short)(hist1);
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}
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|
|
|
stream->adpcm_history1_32=hist1;
|
|
stream->adpcm_step_index=step_index;
|
|
}
|
|
|
|
|
|
void decode_eacs_ima(VGMSTREAM * vgmstream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do, int channel) {
|
|
int i;
|
|
VGMSTREAMCHANNEL * stream = &(vgmstream->ch[channel]);
|
|
|
|
int32_t sample_count=0;
|
|
int32_t hist1=stream->adpcm_history1_32;
|
|
int step_index = stream->adpcm_step_index;
|
|
|
|
vgmstream->get_high_nibble=!vgmstream->get_high_nibble;
|
|
|
|
if((first_sample) && (channelspacing==1))
|
|
vgmstream->get_high_nibble=!vgmstream->get_high_nibble;
|
|
|
|
for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
|
|
int step = ADPCMTable[step_index];
|
|
uint8_t sample_byte;
|
|
int sample_nibble;
|
|
int sample_decoded;
|
|
int delta;
|
|
|
|
sample_byte = read_8bit(stream->offset+i,stream->streamfile);
|
|
sample_nibble = (sample_byte >> (vgmstream->get_high_nibble?0:4))&0xf;
|
|
|
|
sample_decoded = hist1;
|
|
delta = step >> 3;
|
|
if (sample_nibble & 1) delta += step >> 2;
|
|
if (sample_nibble & 2) delta += step >> 1;
|
|
if (sample_nibble & 4) delta += step;
|
|
if (sample_nibble & 8)
|
|
sample_decoded -= delta;
|
|
else
|
|
sample_decoded += delta;
|
|
|
|
hist1=clamp16(sample_decoded);
|
|
|
|
step_index += IMA_IndexTable[sample_nibble&0x7];
|
|
if (step_index < 0) step_index=0;
|
|
if (step_index > 88) step_index=88;
|
|
|
|
outbuf[sample_count]=(short)(hist1);
|
|
}
|
|
|
|
stream->adpcm_history1_32=hist1;
|
|
stream->adpcm_step_index=step_index;
|
|
}
|
|
|
|
void decode_ima(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do) {
|
|
int i;
|
|
|
|
int32_t sample_count=0;
|
|
int32_t hist1=stream->adpcm_history1_32;
|
|
int step_index = stream->adpcm_step_index;
|
|
|
|
for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
|
|
int step = ADPCMTable[step_index];
|
|
uint8_t sample_byte;
|
|
int sample_nibble;
|
|
int sample_decoded;
|
|
int delta;
|
|
|
|
sample_byte = read_8bit(stream->offset+i/2,stream->streamfile);
|
|
sample_nibble = (sample_byte >> (i&1?4:0))&0xf;
|
|
|
|
sample_decoded = hist1;
|
|
delta = step >> 3;
|
|
if (sample_nibble & 1) delta += step >> 2;
|
|
if (sample_nibble & 2) delta += step >> 1;
|
|
if (sample_nibble & 4) delta += step;
|
|
if (sample_nibble & 8)
|
|
sample_decoded -= delta;
|
|
else
|
|
sample_decoded += delta;
|
|
|
|
hist1=clamp16(sample_decoded);
|
|
|
|
step_index += IMA_IndexTable[sample_nibble&0x7];
|
|
if (step_index < 0) step_index=0;
|
|
if (step_index > 88) step_index=88;
|
|
|
|
outbuf[sample_count]=(short)(hist1);
|
|
}
|
|
|
|
stream->adpcm_history1_32=hist1;
|
|
stream->adpcm_step_index=step_index;
|
|
}
|
|
|
|
void decode_apple_ima4(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do) {
|
|
int i;
|
|
|
|
int32_t sample_count=0;
|
|
int16_t hist1=stream->adpcm_history1_16;
|
|
int step_index = stream->adpcm_step_index;
|
|
|
|
off_t packet_offset = stream->offset + first_sample/64*34;
|
|
|
|
first_sample = first_sample % 64;
|
|
|
|
if (first_sample == 0)
|
|
{
|
|
hist1 = (int16_t)((uint16_t)read_16bitBE(packet_offset,stream->streamfile) & 0xff80);
|
|
step_index = read_8bit(packet_offset+1,stream->streamfile) & 0x7f;
|
|
}
|
|
|
|
for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
|
|
int step = ADPCMTable[step_index];
|
|
uint8_t sample_byte;
|
|
int sample_nibble;
|
|
int sample_decoded;
|
|
int delta;
|
|
|
|
sample_byte = read_8bit(packet_offset+2+i/2,stream->streamfile);
|
|
sample_nibble = (sample_byte >> (i&1?4:0))&0xf;
|
|
|
|
sample_decoded = hist1;
|
|
delta = step >> 3;
|
|
if (sample_nibble & 1) delta += step >> 2;
|
|
if (sample_nibble & 2) delta += step >> 1;
|
|
if (sample_nibble & 4) delta += step;
|
|
if (sample_nibble & 8)
|
|
sample_decoded -= delta;
|
|
else
|
|
sample_decoded += delta;
|
|
|
|
hist1=clamp16(sample_decoded);
|
|
|
|
step_index += IMA_IndexTable[sample_nibble&0x7];
|
|
if (step_index < 0) step_index=0;
|
|
if (step_index > 88) step_index=88;
|
|
|
|
outbuf[sample_count]=(short)(hist1);
|
|
}
|
|
|
|
stream->adpcm_history1_16=hist1;
|
|
stream->adpcm_step_index=step_index;
|
|
}
|
|
|
|
void decode_snds_ima(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do, int channel) {
|
|
int i;
|
|
|
|
int32_t sample_count=0;
|
|
int32_t hist1=stream->adpcm_history1_32;
|
|
int step_index = stream->adpcm_step_index;
|
|
|
|
for (i=first_sample,sample_count=0; i<first_sample+samples_to_do; i++,sample_count+=channelspacing) {
|
|
int step;
|
|
uint8_t sample_byte;
|
|
int sample_nibble;
|
|
int sample_decoded;
|
|
int delta;
|
|
|
|
sample_byte = read_8bit(stream->offset+i,stream->streamfile);
|
|
sample_nibble = (sample_byte >> (channel==0?4:0))&0xf;
|
|
|
|
// update step before doing current sample
|
|
step_index += IMA_IndexTable[sample_nibble];
|
|
if (step_index < 0) step_index=0;
|
|
if (step_index > 88) step_index=88;
|
|
step = ADPCMTable[step_index];
|
|
|
|
delta = (sample_nibble & 7) * step / 4 + step / 8;
|
|
if (sample_nibble & 8) delta = -delta;
|
|
sample_decoded = hist1 + delta;
|
|
|
|
hist1=clamp16(sample_decoded);
|
|
|
|
outbuf[sample_count]=(short)(hist1);
|
|
}
|
|
|
|
stream->adpcm_history1_32=hist1;
|
|
stream->adpcm_step_index=step_index;
|
|
}
|
|
|