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a5843ef470
@ -510,43 +510,41 @@ void decode_eacs_ima(VGMSTREAM * vgmstream, sample * outbuf, int channelspacing,
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}
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void decode_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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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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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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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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sample_nibble = (sample_byte >> (i&1?4:0))&0xf;
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sample_byte = read_8bit(stream->offset + i / 2, stream->streamfile);
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sample_nibble = (sample_byte >> (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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sample_decoded = hist1 << 3;
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hist1=clamp16(sample_decoded);
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delta = step * (sample_nibble & 7) * 2 + 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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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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hist1 = clamp16(sample_decoded >> 3);
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outbuf[sample_count]=(short)(hist1);
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}
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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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stream->adpcm_history1_32=hist1;
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stream->adpcm_step_index=step_index;
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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_apple_ima4(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do) {
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