| /* |
| * 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 "BP_1I_D16F32Cll_TRC_WRA_01_Private.h" |
| #include "LVM_Macros.h" |
| |
| |
| /************************************************************************** |
| ASSUMPTIONS: |
| COEFS- |
| pBiquadState->coefs[0] is A0, |
| pBiquadState->coefs[1] is -B2, |
| pBiquadState->coefs[2] is -B1, these are in Q30 format |
| |
| DELAYS- |
| pBiquadState->pDelays[0] is x(n-1)L in Q0 format |
| pBiquadState->pDelays[1] is x(n-2)L in Q0 format |
| pBiquadState->pDelays[2] is y(n-1)L in Q16 format |
| pBiquadState->pDelays[3] is y(n-2)L in Q16 format |
| ***************************************************************************/ |
| |
| void BP_1I_D16F32C30_TRC_WRA_01 ( Biquad_Instance_t *pInstance, |
| LVM_INT16 *pDataIn, |
| LVM_INT16 *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= (A0 (Q30) * (x(n)L (Q0) - x(n-2)L (Q0) ) >>14) in Q16 |
| templ= (LVM_INT32) *pDataIn-pBiquadState->pDelays[1]; |
| MUL32x32INTO32(pBiquadState->coefs[0],templ,ynL,14) |
| |
| // ynL+= ((-B2 (Q30) * y(n-2)L (Q16) ) >>30) in Q16 |
| MUL32x32INTO32(pBiquadState->coefs[1],pBiquadState->pDelays[3],templ,30) |
| ynL+=templ; |
| |
| // ynL+= ((-B1 (Q30) * y(n-1)L (Q16) ) >>30) in Q16 |
| MUL32x32INTO32(pBiquadState->coefs[2],pBiquadState->pDelays[2],templ,30) |
| ynL+=templ; |
| |
| /************************************************************************** |
| UPDATING THE DELAYS |
| ***************************************************************************/ |
| pBiquadState->pDelays[3]=pBiquadState->pDelays[2]; // y(n-2)L=y(n-1)L |
| pBiquadState->pDelays[1]=pBiquadState->pDelays[0]; // x(n-2)L=x(n-1)L |
| pBiquadState->pDelays[2]=ynL; // Update y(n-1)L in Q16 |
| pBiquadState->pDelays[0]=(*pDataIn++); // Update x(n-1)L in Q0 |
| |
| /************************************************************************** |
| WRITING THE OUTPUT |
| ***************************************************************************/ |
| *pDataOut++=(LVM_INT16)(ynL>>16); // Write Left output in Q0 |
| |
| } |
| |
| } |
| |
