35#if !defined(_SPANDSP_BIQUAD_H_) 
   36#define _SPANDSP_BIQUAD_H_ 
   49#if FIRST_ORDER_NOISE_SHAPING 
   51#elif SECOND_ORDER_NOISE_SHAPING 
   57#if defined(__cplusplus) 
   78#if FIRST_ORDER_NOISE_SHAPING 
   80#elif SECOND_ORDER_NOISE_SHAPING 
   92    z0 = sample*bq->gain + bq->z1*bq->a1 + bq->z2*bq->a2;
 
   93    y = z0 + bq->z1*bq->b1 + bq->z2*bq->b2;
 
   97#if FIRST_ORDER_NOISE_SHAPING 
   99    bq->residue = y & 0x7FFF;
 
  100#elif SECOND_ORDER_NOISE_SHAPING 
  101    y += (2*bq->residue1 - bq->residue2);
 
  102    bq->residue2 = bq->residue1;
 
  103    bq->residue1 = y & 0x7FFF;
 
  110#if defined(__cplusplus)