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DspTool dump

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a dinosaur
2023-03-19 08:41:31 +11:00
parent 9cdae38cbf
commit ac89564669
6 changed files with 810 additions and 0 deletions
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101
dsptools/decode.c Normal file
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#include <stdint.h>
#include "dsptool.h"
#include <limits.h>
#define MIN(a,b) (((a)<(b))?(a):(b))
#define MAX(a,b) (((a)>(b))?(a):(b))
inline int DivideByRoundUp(int dividend, int divisor)
{
return (dividend + divisor - 1) / divisor;
}
inline char GetHighNibble(char value)
{
return value >> 4 & 0xF;
}
inline char GetLowNibble(char value)
{
return value & 0xF;
}
inline short Clamp16(int value)
{
if (value > SHRT_MAX)
return SHRT_MAX;
if (value < SHRT_MIN)
return SHRT_MIN;
return 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;
int frameCount = DivideByRoundUp(samples, SAMPLES_PER_FRAME);
int samplesRemaining = samples;
for (int 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];
int samplesToRead = MIN(SAMPLES_PER_FRAME, samplesRemaining);
for (int s = 0; s < samplesToRead; s++)
{
int sample = s % 2 == 0 ? GetHighNibble(*src) : GetLowNibble(*src++);
sample = sample >= 8 ? sample - 16 : sample;
sample = (((scale * sample) << 11) + 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;
char ps = 0;
int frameCount = DivideByRoundUp(samples, SAMPLES_PER_FRAME);
int 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];
int samplesToRead = MIN(SAMPLES_PER_FRAME, samplesRemaining);
for (int s = 0; s < samplesToRead; s++)
{
int sample = s % 2 == 0 ? GetHighNibble(*src) : GetLowNibble(*src++);
sample = sample >= 8 ? sample - 16 : sample;
sample = (((scale * sample) << 11) + 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;
}