| /* |
| * Copyright (C) 2004-2010 NXP Software |
| * Copyright (C) 2010 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "BIQUAD.h" |
| #include "FO_1I_D32F32Cll_TRC_WRA_01_Private.h" |
| #include "LVM_Macros.h" |
| |
| |
| /************************************************************************** |
| ASSUMPTIONS: |
| COEFS- |
| pBiquadState->coefs[0] is A1, |
| pBiquadState->coefs[1] is A0, |
| pBiquadState->coefs[2] is -B1, these are in Q31 format |
| |
| DELAYS- |
| pBiquadState->pDelays[0] is x(n-1)L in Q0 format |
| pBiquadState->pDelays[1] is y(n-1)L in Q0 format |
| ***************************************************************************/ |
| #ifdef BUILD_FLOAT |
| void FO_1I_D32F32C31_TRC_WRA_01( Biquad_FLOAT_Instance_t *pInstance, |
| LVM_FLOAT *pDataIn, |
| LVM_FLOAT *pDataOut, |
| LVM_INT16 NrSamples) |
| { |
| LVM_FLOAT ynL,templ; |
| LVM_INT16 ii; |
| PFilter_State_FLOAT pBiquadState = (PFilter_State_FLOAT) pInstance; |
| |
| for (ii = NrSamples; ii != 0; ii--) |
| { |
| |
| /************************************************************************** |
| PROCESSING OF THE LEFT CHANNEL |
| ***************************************************************************/ |
| // ynL=A1 * x(n-1)L |
| ynL = pBiquadState->coefs[0] * pBiquadState->pDelays[0]; |
| |
| // ynL+=A0 * x(n)L |
| templ = pBiquadState->coefs[1] * (*pDataIn); |
| ynL += templ; |
| |
| // ynL+= (-B1 * y(n-1)L |
| templ = pBiquadState->coefs[2] * pBiquadState->pDelays[1]; |
| ynL += templ; |
| |
| /************************************************************************** |
| UPDATING THE DELAYS |
| ***************************************************************************/ |
| pBiquadState->pDelays[1] = ynL; // Update y(n-1)L |
| pBiquadState->pDelays[0] = (*pDataIn++); // Update x(n-1)L |
| |
| /************************************************************************** |
| WRITING THE OUTPUT |
| ***************************************************************************/ |
| *pDataOut++ = (LVM_FLOAT)ynL; // Write Left output in Q0 |
| } |
| |
| } |
| #else |
| void FO_1I_D32F32C31_TRC_WRA_01( Biquad_Instance_t *pInstance, |
| LVM_INT32 *pDataIn, |
| LVM_INT32 *pDataOut, |
| LVM_INT16 NrSamples) |
| { |
| LVM_INT32 ynL,templ; |
| LVM_INT16 ii; |
| PFilter_State pBiquadState = (PFilter_State) pInstance; |
| |
| for (ii = NrSamples; ii != 0; ii--) |
| { |
| |
| /************************************************************************** |
| PROCESSING OF THE LEFT CHANNEL |
| ***************************************************************************/ |
| // ynL=A1 (Q31) * x(n-1)L (Q0) >>31 in Q0 |
| MUL32x32INTO32(pBiquadState->coefs[0],pBiquadState->pDelays[0],ynL,31) |
| |
| // ynL+=A0 (Q31) * x(n)L (Q0) >> 31 in Q0 |
| MUL32x32INTO32(pBiquadState->coefs[1],*pDataIn,templ,31) |
| ynL+=templ; |
| |
| // ynL+= (-B1 (Q31) * y(n-1)L (Q0) ) >> 31 in Q0 |
| MUL32x32INTO32(pBiquadState->coefs[2],pBiquadState->pDelays[1],templ,31) |
| ynL+=templ; |
| |
| /************************************************************************** |
| UPDATING THE DELAYS |
| ***************************************************************************/ |
| pBiquadState->pDelays[1]=ynL; // Update y(n-1)L in Q0 |
| pBiquadState->pDelays[0]=(*pDataIn++); // Update x(n-1)L in Q0 |
| |
| /************************************************************************** |
| WRITING THE OUTPUT |
| ***************************************************************************/ |
| *pDataOut++=(LVM_INT32)ynL; // Write Left output in Q0 |
| } |
| |
| } |
| #endif |