diff options
Diffstat (limited to 'media/libeffects/lvm/lib/Common/src/FO_2I_D16F32C15_LShx_TRC_WRA_01.c')
| -rwxr-xr-x | media/libeffects/lvm/lib/Common/src/FO_2I_D16F32C15_LShx_TRC_WRA_01.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/media/libeffects/lvm/lib/Common/src/FO_2I_D16F32C15_LShx_TRC_WRA_01.c b/media/libeffects/lvm/lib/Common/src/FO_2I_D16F32C15_LShx_TRC_WRA_01.c new file mode 100755 index 0000000..4b219a2 --- /dev/null +++ b/media/libeffects/lvm/lib/Common/src/FO_2I_D16F32C15_LShx_TRC_WRA_01.c @@ -0,0 +1,137 @@ +/* + * 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. + */ + +/************************************************************************/ +/* */ +/* Project:: */ +/* $Author: beq07716 $*/ +/* $Revision: 1000 $*/ +/* $Date: 2010-06-28 13:08:20 +0200 (Mon, 28 Jun 2010) $*/ +/* */ +/************************************************************************/ + +#include "BIQUAD.h" +#include "FO_2I_D16F32Css_LShx_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 Q15 format +pBiquadState->Shift is Shift value +DELAYS- +pBiquadState->pDelays[0] is x(n-1)L in Q15 format +pBiquadState->pDelays[1] is y(n-1)L in Q30 format +pBiquadState->pDelays[2] is x(n-1)R in Q15 format +pBiquadState->pDelays[3] is y(n-1)R in Q30 format +***************************************************************************/ + +void FO_2I_D16F32C15_LShx_TRC_WRA_01(Biquad_Instance_t *pInstance, + LVM_INT16 *pDataIn, + LVM_INT16 *pDataOut, + LVM_INT16 NrSamples) + { + LVM_INT32 ynL,ynR; + LVM_INT32 Temp; + LVM_INT32 NegSatValue; + LVM_INT16 ii; + LVM_INT16 Shift; + PFilter_State pBiquadState = (PFilter_State) pInstance; + + NegSatValue = LVM_MAXINT_16 +1; + NegSatValue = -NegSatValue; + + Shift = pBiquadState->Shift; + + + for (ii = NrSamples; ii != 0; ii--) + { + + /************************************************************************** + PROCESSING OF THE LEFT CHANNEL + ***************************************************************************/ + + // ynL =A1 (Q15) * x(n-1)L (Q15) in Q30 + ynL=(LVM_INT32)pBiquadState->coefs[0]* pBiquadState->pDelays[0]; + // ynR =A1 (Q15) * x(n-1)R (Q15) in Q30 + ynR=(LVM_INT32)pBiquadState->coefs[0]* pBiquadState->pDelays[2]; + + + // ynL+=A0 (Q15) * x(n)L (Q15) in Q30 + ynL+=(LVM_INT32)pBiquadState->coefs[1]* (*pDataIn); + // ynR+=A0 (Q15) * x(n)L (Q15) in Q30 + ynR+=(LVM_INT32)pBiquadState->coefs[1]* (*(pDataIn+1)); + + + // ynL += (-B1 (Q15) * y(n-1)L (Q30) ) in Q30 + MUL32x16INTO32(pBiquadState->pDelays[1],pBiquadState->coefs[2],Temp,15); + ynL +=Temp; + // ynR += (-B1 (Q15) * y(n-1)R (Q30) ) in Q30 + MUL32x16INTO32(pBiquadState->pDelays[3],pBiquadState->coefs[2],Temp,15); + ynR +=Temp; + + + /************************************************************************** + UPDATING THE DELAYS + ***************************************************************************/ + pBiquadState->pDelays[1]=ynL; // Update y(n-1)L in Q30 + pBiquadState->pDelays[0]=(*pDataIn++); // Update x(n-1)L in Q15 + + pBiquadState->pDelays[3]=ynR; // Update y(n-1)R in Q30 + pBiquadState->pDelays[2]=(*pDataIn++); // Update x(n-1)R in Q15 + + /************************************************************************** + WRITING THE OUTPUT + ***************************************************************************/ + /*Apply shift: Instead of left shift on 16-bit result, right shift of (15-shift) is applied + for better SNR*/ + ynL = ynL>>(15-Shift); + ynR = ynR>>(15-Shift); + + /*Saturate results*/ + if(ynL > LVM_MAXINT_16) + { + ynL = LVM_MAXINT_16; + } + else + { + if(ynL < NegSatValue) + { + ynL = NegSatValue; + } + } + + if(ynR > LVM_MAXINT_16) + { + ynR = LVM_MAXINT_16; + } + else + { + if(ynR < NegSatValue) + { + ynR = NegSatValue; + } + } + + *pDataOut++=(LVM_INT16)ynL; + *pDataOut++=(LVM_INT16)ynR; + } + + } + |