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dsptool: refactor

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a dinosaur
2023-03-19 09:58:26 +11:00
parent ac89564669
commit 99bf061438
9 changed files with 848 additions and 804 deletions
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101
dsptools/libdsptool/decode.c Normal file
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/* (c) 2017 Alex Barney (MIT) */
#include <stdint.h>
#include "common.h"
#include "dsptool.h"
static inline uint8_t GetHighNibble(uint8_t value)
{
return value >> 4 & 0xF;
}
static inline uint8_t GetLowNibble(uint8_t value)
{
return value & 0xF;
}
static inline int16_t Clamp16(int value)
{
if (value > INT16_MAX)
return INT16_MAX;
if (value < INT16_MIN)
return INT16_MIN;
return (int16_t)value;
}
void decode(uint8_t* src, int16_t* dst, ADPCMINFO* cxt, uint32_t samples)
{
short hist1 = cxt->yn1;
short hist2 = cxt->yn2;
short* coefs = cxt->coef;
uint32_t frameCount = (samples + SAMPLES_PER_FRAME - 1) / SAMPLES_PER_FRAME;
uint32_t samplesRemaining = samples;
for (uint32_t i = 0; i < frameCount; i++)
{
int predictor = GetHighNibble(*src);
int scale = 1 << GetLowNibble(*src++);
short coef1 = coefs[predictor * 2];
short coef2 = coefs[predictor * 2 + 1];
uint32_t samplesToRead = MIN(SAMPLES_PER_FRAME, samplesRemaining);
for (uint32_t s = 0; s < samplesToRead; s++)
{
int sample = (s & 0x1)
? GetLowNibble(*src++)
: GetHighNibble(*src);
sample = sample >= 8 ? sample - 16 : sample;
sample = (scale * sample) << 11;
sample = (sample + 1024 + (coef1 * hist1 + coef2 * hist2)) >> 11;
short finalSample = Clamp16(sample);
hist2 = hist1;
hist1 = finalSample;
*dst++ = finalSample;
}
samplesRemaining -= samplesToRead;
}
}
void getLoopContext(uint8_t* src, ADPCMINFO* cxt, uint32_t samples)
{
short hist1 = cxt->yn1;
short hist2 = cxt->yn2;
short* coefs = cxt->coef;
uint8_t ps = 0;
int frameCount = (int)((samples + SAMPLES_PER_FRAME - 1) / SAMPLES_PER_FRAME);
uint32_t samplesRemaining = samples;
for (int i = 0; i < frameCount; i++)
{
ps = *src;
int predictor = GetHighNibble(*src);
int scale = 1 << GetLowNibble(*src++);
short coef1 = coefs[predictor * 2];
short coef2 = coefs[predictor * 2 + 1];
uint32_t samplesToRead = MIN(SAMPLES_PER_FRAME, samplesRemaining);
for (uint32_t s = 0; s < samplesToRead; s++)
{
int sample = (s & 0x1)
? GetLowNibble(*src++)
: GetHighNibble(*src);
sample = sample >= 8 ? sample - 16 : sample;
sample = (scale * sample) << 11;
sample = (sample + 1024 + (coef1 * hist1 + coef2 * hist2)) >> 11;
short finalSample = Clamp16(sample);
hist2 = hist1;
hist1 = finalSample;
}
samplesRemaining -= samplesToRead;
}
cxt->loop_pred_scale = ps;
cxt->loop_yn1 = hist1;
cxt->loop_yn2 = hist2;
}