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OKIADPCMEncoder
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@ -108,54 +108,4 @@ class OKIADPCM_Decoder
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int32 CurSample;
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int32 StepSizeIndex;
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};
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template <OKIADPCM_Chip CHIP_TYPE>
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class OKIADPCM_Encoder
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{
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public:
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OKIADPCM_Encoder()
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{
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Accum = 0x800;
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StepSizeIndex = 0;
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}
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~OKIADPCM_Encoder()
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{
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}
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uint8 EncodeSample(uint16 in_sample)
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{
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uint8 nibble = 0;
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int32 sample_delta = in_sample - Accum;
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int piece;
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piece = (abs(sample_delta) * 4 / OKIADPCM_StepSizes[StepSizeIndex]);
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if(piece > 0x7)
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piece = 0x7;
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nibble = ((uint32)(sample_delta >> 31) & 0x8) | piece;
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// Update Accum and StepSizeIndex!
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Accum += OKIADPCM_DeltaTable[StepSizeIndex][nibble];
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StepSizeIndex += OKIADPCM_StepIndexDeltas[nibble];
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if(Accum > 0xFFF) Accum = 0xFFF;
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if(Accum < 0) Accum = 0;
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if(StepSizeIndex < 0)
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StepSizeIndex = 0;
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if(StepSizeIndex > 48)
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StepSizeIndex = 48;
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return(nibble);
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}
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private:
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int32 Accum;
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int32 StepSizeIndex;
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OKIADPCM_Chip ChipType;
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};
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#endif
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