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      1 /*
      2  * Copyright (C) 2004-2010 NXP Software
      3  * Copyright (C) 2010 The Android Open Source Project
      4  *
      5  * Licensed under the Apache License, Version 2.0 (the "License");
      6  * you may not use this file except in compliance with the License.
      7  * You may obtain a copy of the License at
      8  *
      9  *      http://www.apache.org/licenses/LICENSE-2.0
     10  *
     11  * Unless required by applicable law or agreed to in writing, software
     12  * distributed under the License is distributed on an "AS IS" BASIS,
     13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14  * See the License for the specific language governing permissions and
     15  * limitations under the License.
     16  */
     17 
     18 #include "BIQUAD.h"
     19 #include "FO_1I_D32F32Cll_TRC_WRA_01_Private.h"
     20 #include "LVM_Macros.h"
     21 
     22 
     23 /**************************************************************************
     24  ASSUMPTIONS:
     25  COEFS-
     26  pBiquadState->coefs[0] is A1,
     27  pBiquadState->coefs[1] is A0,
     28  pBiquadState->coefs[2] is -B1, these are in Q31 format
     29 
     30  DELAYS-
     31  pBiquadState->pDelays[0] is x(n-1)L in Q0 format
     32  pBiquadState->pDelays[1] is y(n-1)L in Q0 format
     33 ***************************************************************************/
     34 #ifdef BUILD_FLOAT
     35 void FO_1I_D32F32C31_TRC_WRA_01( Biquad_FLOAT_Instance_t       *pInstance,
     36                                  LVM_FLOAT               *pDataIn,
     37                                  LVM_FLOAT               *pDataOut,
     38                                  LVM_INT16               NrSamples)
     39     {
     40         LVM_FLOAT  ynL,templ;
     41         LVM_INT16  ii;
     42         PFilter_State_FLOAT pBiquadState = (PFilter_State_FLOAT) pInstance;
     43 
     44         for (ii = NrSamples; ii != 0; ii--)
     45         {
     46 
     47             /**************************************************************************
     48                             PROCESSING OF THE LEFT CHANNEL
     49             ***************************************************************************/
     50             // ynL=A1  * x(n-1)L
     51             ynL = pBiquadState->coefs[0] * pBiquadState->pDelays[0];
     52 
     53             // ynL+=A0  * x(n)L
     54             templ = pBiquadState->coefs[1] * (*pDataIn);
     55             ynL += templ;
     56 
     57             // ynL+=  (-B1  * y(n-1)L
     58             templ = pBiquadState->coefs[2] * pBiquadState->pDelays[1];
     59             ynL += templ;
     60 
     61             /**************************************************************************
     62                             UPDATING THE DELAYS
     63             ***************************************************************************/
     64             pBiquadState->pDelays[1] = ynL; // Update y(n-1)L
     65             pBiquadState->pDelays[0] = (*pDataIn++); // Update x(n-1)L
     66 
     67             /**************************************************************************
     68                             WRITING THE OUTPUT
     69             ***************************************************************************/
     70             *pDataOut++ = (LVM_FLOAT)ynL; // Write Left output in Q0
     71         }
     72 
     73     }
     74 #else
     75 void FO_1I_D32F32C31_TRC_WRA_01( Biquad_Instance_t       *pInstance,
     76                                  LVM_INT32               *pDataIn,
     77                                  LVM_INT32               *pDataOut,
     78                                  LVM_INT16               NrSamples)
     79     {
     80         LVM_INT32  ynL,templ;
     81         LVM_INT16  ii;
     82         PFilter_State pBiquadState = (PFilter_State) pInstance;
     83 
     84         for (ii = NrSamples; ii != 0; ii--)
     85         {
     86 
     87             /**************************************************************************
     88                             PROCESSING OF THE LEFT CHANNEL
     89             ***************************************************************************/
     90             // ynL=A1 (Q31) * x(n-1)L (Q0) >>31 in Q0
     91             MUL32x32INTO32(pBiquadState->coefs[0],pBiquadState->pDelays[0],ynL,31)
     92 
     93             // ynL+=A0 (Q31) * x(n)L (Q0) >> 31 in Q0
     94             MUL32x32INTO32(pBiquadState->coefs[1],*pDataIn,templ,31)
     95             ynL+=templ;
     96 
     97             // ynL+=  (-B1 (Q31) * y(n-1)L (Q0) ) >> 31 in Q0
     98             MUL32x32INTO32(pBiquadState->coefs[2],pBiquadState->pDelays[1],templ,31)
     99             ynL+=templ;
    100 
    101             /**************************************************************************
    102                             UPDATING THE DELAYS
    103             ***************************************************************************/
    104             pBiquadState->pDelays[1]=ynL; // Update y(n-1)L in Q0
    105             pBiquadState->pDelays[0]=(*pDataIn++); // Update x(n-1)L in Q0
    106 
    107             /**************************************************************************
    108                             WRITING THE OUTPUT
    109             ***************************************************************************/
    110             *pDataOut++=(LVM_INT32)ynL; // Write Left output in Q0
    111         }
    112 
    113     }
    114 #endif
    115