| #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]; |
| } |
| } |