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| #include "ref.h"
|
| void ref_std_f32(
| float32_t * pSrc,
| uint32_t blockSize,
| float32_t * pResult)
| {
| uint32_t i;
| float32_t sum=0, sumsq=0;
|
| if (blockSize == 1)
| {
| *pResult = 0;
| return;
| }
|
| for(i=0;i<blockSize;i++)
| {
| sum += pSrc[i];
| sumsq += pSrc[i] * pSrc[i];
| }
| *pResult = sqrtf((sumsq - sum * sum / (float32_t)blockSize) / ((float32_t)blockSize - 1));
| }
|
| void ref_std_q31(
| q31_t * pSrc,
| uint32_t blockSize,
| q31_t * pResult)
| {
| uint32_t i;
| q63_t sum=0, sumsq=0;
| q31_t in;
|
| if (blockSize == 1)
| {
| *pResult = 0;
| return;
| }
|
| for(i=0;i<blockSize;i++)
| {
| in = pSrc[i] >> 8;
| sum += in;
| sumsq += (q63_t)in * in;
| }
| sumsq /= (q63_t)(blockSize - 1);
| sum = sum * sum / (q63_t)(blockSize * (blockSize - 1));
| *pResult = (q31_t)(sqrtf((float)( (sumsq - sum) >> 15) / 2147483648.0f ) * 2147483648.0f);
| }
|
| void ref_std_q15(
| q15_t * pSrc,
| uint32_t blockSize,
| q15_t * pResult)
| {
| uint32_t i;
| q31_t sum=0;
| q63_t sumsq=0;
|
| if (blockSize == 1)
| {
| *pResult = 0;
| return;
| }
|
| for(i=0;i<blockSize;i++)
| {
| sum += pSrc[i];
| sumsq += (q63_t)pSrc[i] * pSrc[i];
| }
| sumsq /= (q63_t)(blockSize - 1);
| sum = (q31_t)((q63_t)sum * sum / (q63_t)(blockSize * (blockSize - 1)));
| *pResult = (q15_t)(sqrtf((float)ref_sat_q15( (sumsq - sum) >> 15) / 32768.0f ) * 32768.0f);
| }
|
|
