#include "ref.h"
|
|
void ref_dct4_f32(
|
const arm_dct4_instance_f32 * S,
|
float32_t * pState,
|
float32_t * pInlineBuffer)
|
{
|
uint32_t n,k;
|
float32_t sum;
|
float32_t pi_by_N = 3.14159265358979f / (float32_t)S->N;
|
float32_t tmp;
|
float32_t normalize = sqrtf(2.0f / (float32_t)S->N);
|
|
for(k=0;k<S->N;k++)
|
{
|
sum=0.0f;
|
tmp = ((float32_t)k + 0.5f)*pi_by_N;
|
for(n=0;n<S->N;n++)
|
{
|
sum += pInlineBuffer[n] * cosf(tmp * ((float32_t)n + 0.5f));
|
}
|
scratchArray[k] = normalize * sum;
|
}
|
|
for(k=0;k<S->N;k++)
|
{
|
pInlineBuffer[k] = scratchArray[k];
|
}
|
}
|
|
void ref_dct4_q31(
|
const arm_dct4_instance_q31 * S,
|
q31_t * pState,
|
q31_t * pInlineBuffer)
|
{
|
arm_dct4_instance_f32 SS;
|
float32_t *fSrc = (float32_t*)pInlineBuffer;
|
uint32_t i;
|
|
SS.N = S->N;
|
|
for(i=0;i<S->N;i++)
|
{
|
//read the q31 data, cast to float, scale down for float
|
fSrc[i] = (float32_t)pInlineBuffer[i] / 2147483648.0f;
|
}
|
|
ref_dct4_f32(&SS,(float32_t*)0,fSrc);
|
|
for(i=0;i<S->N;i++)
|
{
|
fSrc[i] = fSrc[i] * 2147483648.0f / (float32_t)S->N ;
|
fSrc[i] += (fSrc[i] > 0) ? 0.5f : -0.5f;
|
pInlineBuffer[i] = (q31_t)fSrc[i];
|
}
|
}
|
|
void ref_dct4_q15(
|
const arm_dct4_instance_q15 * S,
|
q15_t * pState,
|
q15_t * pInlineBuffer)
|
{
|
arm_dct4_instance_f32 SS;
|
float32_t *fSrc = (float32_t*)pInlineBuffer;
|
uint32_t i;
|
|
SS.N = S->N;
|
|
for(i=0;i<S->N;i++)
|
{
|
//read the q15 data, cast to float, scale down for float, place in temporary buffer
|
scratchArray[i] = (float32_t)pInlineBuffer[i] / 32768.0f;
|
}
|
|
for(i=0;i<S->N;i++)
|
{
|
//copy from temp buffer to final buffer
|
fSrc[i] = scratchArray[i];
|
}
|
|
ref_dct4_f32(&SS,(float32_t*)0,fSrc);
|
|
for(i=0;i<S->N;i++)
|
{
|
fSrc[i] = fSrc[i] * 32768.0f / (float32_t)S->N;
|
fSrc[i] += (fSrc[i] > 0) ? 0.5f : -0.5f;
|
pInlineBuffer[i] = (q15_t)fSrc[i];
|
}
|
}
|
