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diff --git a/media/libeffects/lvm/lib/SpectrumAnalyzer/src/LVPSA_Control.c b/media/libeffects/lvm/lib/SpectrumAnalyzer/src/LVPSA_Control.c
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+++ b/media/libeffects/lvm/lib/SpectrumAnalyzer/src/LVPSA_Control.c
@@ -0,0 +1,715 @@
+/*
+ * 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:: PSA_01_ARMC_01 */
+/* $Author: beq07716 $*/
+/* $Revision: 1006 $*/
+/* $Date: 2010-06-28 14:01:47 +0200 (Mon, 28 Jun 2010) $*/
+/* */
+/************************************************************************/
+#include "LVPSA.h"
+#include "LVPSA_Private.h"
+#include "VectorArithmetic.h"
+
+#define LOW_FREQ 298 /* 32768/110 for low test frequency */
+#define HIGH_FREQ 386 /* 32768/85 for high test frequency */
+
+LVPSA_RETURN LVPSA_SetBPFiltersType ( LVPSA_InstancePr_t *pInst,
+ LVPSA_ControlParams_t *pParams );
+
+LVPSA_RETURN LVPSA_SetQPFCoefficients( LVPSA_InstancePr_t *pInst,
+ LVPSA_ControlParams_t *pParams );
+
+LVPSA_RETURN LVPSA_BPSinglePrecCoefs( LVM_UINT16 Fs,
+ LVPSA_FilterParam_t *pFilterParams,
+ BP_C16_Coefs_t *pCoefficients);
+
+LVPSA_RETURN LVPSA_BPDoublePrecCoefs( LVM_UINT16 Fs,
+ LVPSA_FilterParam_t *pFilterParams,
+ BP_C32_Coefs_t *pCoefficients);
+
+LVPSA_RETURN LVPSA_BPDoublePrecCoefs( LVM_UINT16 Fs,
+ LVPSA_FilterParam_t *pFilterParams,
+ BP_C32_Coefs_t *pCoefficients);
+
+LVPSA_RETURN LVPSA_SetBPFCoefficients( LVPSA_InstancePr_t *pInst,
+ LVPSA_ControlParams_t *pParams );
+
+LVPSA_RETURN LVPSA_ClearFilterHistory( LVPSA_InstancePr_t *pInst);
+
+
+
+
+/************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_Control */
+/* */
+/* DESCRIPTION: */
+/* Give some new control parameters to the module. */
+/* */
+/* PARAMETERS: */
+/* hInstance Pointer to the instance */
+/* NewParams Structure that contains the new parameters */
+/* */
+/* RETURNS: */
+/* LVPSA_OK Succeeds */
+/* otherwise Error due to bad parameters */
+/* */
+/************************************************************************************/
+LVPSA_RETURN LVPSA_Control ( pLVPSA_Handle_t hInstance,
+ LVPSA_ControlParams_t *pNewParams )
+{
+
+ LVPSA_InstancePr_t *pLVPSA_Inst = (LVPSA_InstancePr_t*)hInstance;
+
+ if((hInstance == LVM_NULL) || (pNewParams == LVM_NULL))
+ {
+ return(LVPSA_ERROR_NULLADDRESS);
+ }
+ if(pNewParams->Fs >= LVPSA_NR_SUPPORTED_RATE)
+ {
+ return(LVPSA_ERROR_INVALIDPARAM);
+ }
+ if(pNewParams->LevelDetectionSpeed >= LVPSA_NR_SUPPORTED_SPEED)
+ {
+ return(LVPSA_ERROR_INVALIDPARAM);
+ }
+
+ pLVPSA_Inst->NewParams = *pNewParams;
+ pLVPSA_Inst->bControlPending = LVM_TRUE;
+
+ return(LVPSA_OK);
+}
+
+/************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_GetControlParams */
+/* */
+/* DESCRIPTION: */
+/* Get the current control parameters of the module */
+/* */
+/* PARAMETERS: */
+/* hInstance Pointer to the instance */
+/* pParams Pointer to an empty control structure */
+/* RETURNS: */
+/* LVPSA_OK Succeeds */
+/* otherwise Error due to bad parameters */
+/* */
+/************************************************************************************/
+LVPSA_RETURN LVPSA_GetControlParams ( pLVPSA_Handle_t hInstance,
+ LVPSA_ControlParams_t *pParams )
+{
+ LVPSA_InstancePr_t *pLVPSA_Inst = (LVPSA_InstancePr_t*)hInstance;
+
+ if((hInstance == LVM_NULL) || (pParams == LVM_NULL))
+ {
+ return(LVPSA_ERROR_NULLADDRESS);
+ }
+
+ pParams->Fs = pLVPSA_Inst->CurrentParams.Fs;
+ pParams->LevelDetectionSpeed = pLVPSA_Inst->CurrentParams.LevelDetectionSpeed;
+
+ return(LVPSA_OK);
+}
+
+
+/************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_GetInitParams */
+/* */
+/* DESCRIPTION: */
+/* Get the initialization parameters of the module */
+/* */
+/* PARAMETERS: */
+/* hInstance Pointer to the instance */
+/* pParams Pointer to an empty control structure */
+/* RETURNS: */
+/* LVPSA_OK Succeeds */
+/* otherwise Error due to bad parameters */
+/* */
+/************************************************************************************/
+LVPSA_RETURN LVPSA_GetInitParams ( pLVPSA_Handle_t hInstance,
+ LVPSA_InitParams_t *pParams )
+{
+ LVPSA_InstancePr_t *pLVPSA_Inst = (LVPSA_InstancePr_t*)hInstance;
+
+ if((hInstance == LVM_NULL) || (pParams == LVM_NULL))
+ {
+ return(LVPSA_ERROR_NULLADDRESS);
+ }
+
+ pParams->SpectralDataBufferDuration = pLVPSA_Inst->SpectralDataBufferDuration;
+ pParams->MaxInputBlockSize = pLVPSA_Inst->MaxInputBlockSize;
+ pParams->nBands = pLVPSA_Inst->nBands;
+ pParams->pFiltersParams = pLVPSA_Inst->pFiltersParams;
+
+ return(LVPSA_OK);
+}
+
+
+/************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_ApplyNewSettings */
+/* */
+/* DESCRIPTION: */
+/* Reinitialize some parameters and changes filters' coefficients if */
+/* some control parameters have changed. */
+/* */
+/* PARAMETERS: */
+/* pInst Pointer to the instance */
+/* */
+/* RETURNS: */
+/* LVPSA_OK Succeeds */
+/* otherwise Error due to bad parameters */
+/* */
+/* NOTES: */
+/* */
+/************************************************************************************/
+LVPSA_RETURN LVPSA_ApplyNewSettings (LVPSA_InstancePr_t *pInst)
+{
+ LVM_UINT16 ii;
+ LVM_UINT16 Freq;
+ LVPSA_ControlParams_t Params;
+ extern LVM_INT16 LVPSA_nSamplesBufferUpdate[];
+ extern LVM_UINT16 LVPSA_SampleRateTab[];
+ extern LVM_UINT16 LVPSA_DownSamplingFactor[];
+
+
+ if(pInst == 0)
+ {
+ return(LVPSA_ERROR_NULLADDRESS);
+ }
+
+ Params = pInst->NewParams;
+
+ /* Modifies filters types and coefficients, clear the taps and
+ re-initializes parameters if sample frequency has changed */
+ if(Params.Fs != pInst->CurrentParams.Fs)
+ {
+ pInst->CurrentParams.Fs = Params.Fs;
+
+ /* Initialize the center freqeuncies as a function of the sample rate */
+ Freq = (LVM_UINT16) ((LVPSA_SampleRateTab[pInst->CurrentParams.Fs]>>1) / (pInst->nBands + 1));
+ for(ii = pInst->nBands; ii > 0; ii--)
+ {
+ pInst->pFiltersParams[ii-1].CenterFrequency = (LVM_UINT16) (Freq * ii);
+ }
+
+ /* Count the number of relevant filters. If the center frequency of the filter is
+ bigger than the nyquist frequency, then the filter is not relevant and doesn't
+ need to be used */
+ for(ii = pInst->nBands; ii > 0; ii--)
+ {
+ if(pInst->pFiltersParams[ii-1].CenterFrequency < (LVPSA_SampleRateTab[pInst->CurrentParams.Fs]>>1))
+ {
+ pInst->nRelevantFilters = ii;
+ break;
+ }
+ }
+ LVPSA_SetBPFiltersType(pInst, &Params);
+ LVPSA_SetBPFCoefficients(pInst, &Params);
+ LVPSA_SetQPFCoefficients(pInst, &Params);
+ LVPSA_ClearFilterHistory(pInst);
+ pInst->nSamplesBufferUpdate = (LVM_UINT16)LVPSA_nSamplesBufferUpdate[Params.Fs];
+ pInst->BufferUpdateSamplesCount = 0;
+ pInst->DownSamplingFactor = LVPSA_DownSamplingFactor[Params.Fs];
+ pInst->DownSamplingCount = 0;
+ for(ii = 0; ii < (pInst->nBands * pInst->SpectralDataBufferLength); ii++)
+ {
+ pInst->pSpectralDataBufferStart[ii] = 0;
+ }
+ for(ii = 0; ii < pInst->nBands; ii++)
+ {
+ pInst->pPreviousPeaks[ii] = 0;
+ }
+ }
+ else
+ {
+ if(Params.LevelDetectionSpeed != pInst->CurrentParams.LevelDetectionSpeed)
+ {
+ LVPSA_SetQPFCoefficients(pInst, &Params);
+ }
+ }
+
+ pInst->CurrentParams = pInst->NewParams;
+
+ return (LVPSA_OK);
+}
+/************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_SetBPFiltersType */
+/* */
+/* DESCRIPTION: */
+/* Sets the filter type based on the BPFilterType. */
+/* */
+/* PARAMETERS: */
+/* pInst Pointer to the instance */
+/* pParams Poniter to conrol parameters */
+/* */
+/* RETURNS: */
+/* LVPSA_OK Always succeeds */
+/* */
+/* NOTES: */
+/* 1. To select the biquad type the follow rules are applied: */
+/* Double precision if (fc <= fs/110) */
+/* Double precision if (fs/110 < fc < fs/85) & (Q>3) */
+/* Single precision otherwise */
+/* */
+/************************************************************************************/
+LVPSA_RETURN LVPSA_SetBPFiltersType ( LVPSA_InstancePr_t *pInst,
+ LVPSA_ControlParams_t *pParams )
+{
+
+ extern LVM_UINT16 LVPSA_SampleRateTab[]; /* Sample rate table */
+ LVM_UINT16 ii; /* Filter band index */
+ LVM_UINT32 fs = (LVM_UINT32)LVPSA_SampleRateTab[(LVM_UINT16)pParams->Fs]; /* Sample rate */
+ LVM_UINT32 fc; /* Filter centre frequency */
+ LVM_INT16 QFactor; /* Filter Q factor */
+
+ for (ii = 0; ii < pInst->nRelevantFilters; ii++)
+ {
+ /*
+ * Get the filter settings
+ */
+ fc = (LVM_UINT32)pInst->pFiltersParams[ii].CenterFrequency; /* Get the band centre frequency */
+ QFactor =(LVM_INT16) pInst->pFiltersParams[ii].QFactor; /* Get the band Q factor */
+
+
+ /*
+ * For each filter set the type of biquad required
+ */
+ pInst->pBPFiltersPrecision[ii] = LVPSA_SimplePrecisionFilter; /* Default to single precision */
+ if ((LOW_FREQ * fs) >= (fc << 15))
+ {
+ /*
+ * fc <= fs/110
+ */
+ pInst->pBPFiltersPrecision[ii] = LVPSA_DoublePrecisionFilter;
+ }
+ else
+ {
+ if (((LOW_FREQ * fs) < (fc << 15)) && ((fc << 15) < (HIGH_FREQ * fs)) && (QFactor > 300))
+ {
+ /*
+ * (fs/110 < fc < fs/85) & (Q>3)
+ */
+ pInst->pBPFiltersPrecision[ii] = LVPSA_DoublePrecisionFilter;
+ }
+ }
+ }
+
+ return(LVPSA_OK);
+}
+
+/************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_SetBPFCoefficients */
+/* */
+/* DESCRIPTION: */
+/* Sets the band pass filter coefficients. This uses the type to select */
+/* single or double precision coefficients. */
+/* */
+/* PARAMETERS: */
+/* pInst Pointer to the instance */
+/* Params Initialisation parameters */
+/* */
+/* RETURNS: */
+/* LVPSA_OK Always succeeds */
+/* */
+/* NOTES: */
+/* */
+/************************************************************************************/
+LVPSA_RETURN LVPSA_SetBPFCoefficients( LVPSA_InstancePr_t *pInst,
+ LVPSA_ControlParams_t *pParams)
+{
+
+ LVM_UINT16 ii;
+
+ /*
+ * Set the coefficients for each band by the init function
+ */
+ for (ii = 0; ii < pInst->nRelevantFilters; ii++)
+ {
+ switch (pInst->pBPFiltersPrecision[ii])
+ {
+ case LVPSA_DoublePrecisionFilter:
+ {
+ BP_C32_Coefs_t Coefficients;
+
+ /*
+ * Calculate the double precision coefficients
+ */
+ LVPSA_BPDoublePrecCoefs((LVM_UINT16)pParams->Fs,
+ &pInst->pFiltersParams[ii],
+ &Coefficients);
+
+ /*
+ * Set the coefficients
+ */
+ BP_1I_D16F32Cll_TRC_WRA_01_Init ( &pInst->pBP_Instances[ii],
+ &pInst->pBP_Taps[ii],
+ &Coefficients);
+ break;
+ }
+
+ case LVPSA_SimplePrecisionFilter:
+ {
+ BP_C16_Coefs_t Coefficients;
+
+ /*
+ * Calculate the single precision coefficients
+ */
+ LVPSA_BPSinglePrecCoefs((LVM_UINT16)pParams->Fs,
+ &pInst->pFiltersParams[ii],
+ &Coefficients);
+
+ /*
+ * Set the coefficients
+ */
+ BP_1I_D16F16Css_TRC_WRA_01_Init ( &pInst->pBP_Instances[ii],
+ &pInst->pBP_Taps[ii],
+ &Coefficients);
+ break;
+ }
+ }
+ }
+
+ return(LVPSA_OK);
+}
+
+
+/************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_SetQPFCoefficients */
+/* */
+/* DESCRIPTION: */
+/* Sets the quasi peak filters coefficients. This uses the chosen */
+/* LevelDetectionSpeed from the control parameters. */
+/* */
+/* PARAMETERS: */
+/* pInst Pointer to the instance */
+/* Params Control parameters */
+/* */
+/* RETURNS: */
+/* LVPSA_OK Always succeeds */
+/* */
+/* NOTES: */
+/* */
+/************************************************************************************/
+LVPSA_RETURN LVPSA_SetQPFCoefficients( LVPSA_InstancePr_t *pInst,
+ LVPSA_ControlParams_t *pParams )
+{
+ LVM_UINT16 ii;
+ LVM_Fs_en Fs = pParams->Fs;
+ QPD_C32_Coefs *pCoefficients;
+ extern QPD_C32_Coefs LVPSA_QPD_Coefs[];
+
+
+ pCoefficients = &LVPSA_QPD_Coefs[(pParams->LevelDetectionSpeed * LVPSA_NR_SUPPORTED_RATE) + Fs];
+
+
+ for (ii = 0; ii < pInst->nRelevantFilters; ii++)
+ {
+ LVPSA_QPD_Init (&pInst->pQPD_States[ii],
+ &pInst->pQPD_Taps[ii],
+ pCoefficients );
+ }
+
+ return(LVPSA_OK);
+
+}
+
+/****************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_BPSinglePrecCoefs */
+/* */
+/* DESCRIPTION: */
+/* Calculate single precision coefficients for a band pass filter */
+/* */
+/* PARAMETERS: */
+/* Fs Sampling frequency index */
+/* pFilterParams Pointer to the filter definition */
+/* pCoefficients Pointer to the coefficients */
+/* */
+/* RETURNS: */
+/* LVPSA_OK Always succeeds */
+/* */
+/* NOTES: */
+/* 1. The equations used are as follows: */
+/* */
+/* t0 = 2 * Pi * Fc / Fs */
+/* */
+/* b2 = -0.5 * (2Q - t0) / (2Q + t0) */
+/* b1 = (0.5 - b2) * cos(t0) */
+/* a0 = (0.5 + b2) / 2 */
+/* */
+/* Where: */
+/* Fc is the centre frequency, DC to Nyquist */
+/* Fs is the sample frequency, 8000 to 48000 in descrete steps */
+/* Q is the Q factor, 0.25 to 12 */
+/* */
+/* 2. This function is entirely based on the LVEQNB_SinglePrecCoefs function */
+/* of the n bands equalizer (LVEQNB */
+/* */
+/****************************************************************************************/
+LVPSA_RETURN LVPSA_BPSinglePrecCoefs( LVM_UINT16 Fs,
+ LVPSA_FilterParam_t *pFilterParams,
+ BP_C16_Coefs_t *pCoefficients)
+{
+
+ extern LVM_INT16 LVPSA_TwoPiOnFsTable[];
+ extern LVM_INT16 LVPSA_CosCoef[];
+
+
+ /*
+ * Intermediate variables and temporary values
+ */
+ LVM_INT32 T0;
+ LVM_INT16 D;
+ LVM_INT32 A0;
+ LVM_INT32 B1;
+ LVM_INT32 B2;
+ LVM_INT32 Dt0;
+ LVM_INT32 B2_Den;
+ LVM_INT32 B2_Num;
+ LVM_INT32 COS_T0;
+ LVM_INT16 coef;
+ LVM_INT32 factor;
+ LVM_INT16 t0;
+ LVM_INT16 i;
+
+
+ /*
+ * Get the filter definition
+ */
+ LVM_UINT16 Frequency = pFilterParams->CenterFrequency;
+ LVM_UINT16 QFactor = pFilterParams->QFactor;
+
+
+ /*
+ * Calculating the intermediate values
+ */
+ T0 = (LVM_INT32)Frequency * LVPSA_TwoPiOnFsTable[Fs]; /* T0 = 2 * Pi * Fc / Fs */
+ D = 3200; /* Floating point value 1.000000 (1*100*2^5) */
+ /* Force D = 1 : the function was originally used for a peaking filter.
+ The D parameter do not exist for a BandPass filter coefficients */
+
+ /*
+ * Calculate the B2 coefficient
+ */
+ Dt0 = D * (T0 >> 10);
+ B2_Den = (LVM_INT32)(((LVM_UINT32)QFactor << 19) + (LVM_UINT32)(Dt0 >> 2));
+ B2_Num = (LVM_INT32)((LVM_UINT32)(Dt0 >> 3) - ((LVM_UINT32)QFactor << 18));
+ B2 = (B2_Num / (B2_Den >> 16)) << 15;
+
+ /*
+ * Calculate the cosine by a polynomial expansion using the equation:
+ *
+ * Cos += coef(n) * t0^n For n = 0 to 6
+ */
+ T0 = (T0 >> 10) * 20859; /* Scale to 1.0 in 16-bit for range 0 to fs/2 */
+ t0 = (LVM_INT16)(T0 >> 16);
+ factor = 0x7fff; /* Initialise to 1.0 for the a0 coefficient */
+ COS_T0 = 0; /* Initialise the error to zero */
+ for (i=1; i<7; i++)
+ {
+ coef = LVPSA_CosCoef[i]; /* Get the nth coefficient */
+ COS_T0 += (factor * coef) >> 5; /* The nth partial sum */
+ factor = (factor * t0) >> 15; /* Calculate t0^n */
+ }
+ COS_T0 = COS_T0 << (LVPSA_CosCoef[0]+6); /* Correct the scaling */
+
+
+ B1 = ((0x40000000 - B2) >> 16) * (COS_T0 >> 16); /* B1 = (0.5 - b2) * cos(t0) */
+ A0 = (0x40000000 + B2) >> 1; /* A0 = (0.5 + b2) / 2 */
+
+ /*
+ * Write coeff into the data structure
+ */
+ pCoefficients->A0 = (LVM_INT16)(A0>>16);
+ pCoefficients->B1 = (LVM_INT16)(B1>>15);
+ pCoefficients->B2 = (LVM_INT16)(B2>>16);
+
+
+ return(LVPSA_OK);
+}
+
+/****************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_BPDoublePrecCoefs */
+/* */
+/* DESCRIPTION: */
+/* Calculate double precision coefficients for a band pass filter */
+/* */
+/* PARAMETERS: */
+/* Fs Sampling frequency index */
+/* pFilterParams Pointer to the filter definition */
+/* pCoefficients Pointer to the coefficients */
+/* */
+/* RETURNS: */
+/* LVPSA_OK Always succeeds */
+/* */
+/* NOTES: */
+/* 1. The equations used are as follows: */
+/* */
+/* t0 = 2 * Pi * Fc / Fs */
+/* */
+/* b2 = -0.5 * (2Q - t0) / (2Q + t0) */
+/* b1 = (0.5 - b2) * (1 - coserr(t0)) */
+/* a0 = (0.5 + b2) / 2 */
+/* */
+/* Where: */
+/* Fc is the centre frequency, DC to Fs/50 */
+/* Fs is the sample frequency, 8000 to 48000 in descrete steps */
+/* Q is the Q factor, 0.25 to 12 (represented by 25 to 1200) */
+/* */
+/* 2. The double precision coefficients are only used when fc is less than fs/85, so */
+/* the cosine of t0 is always close to 1.0. Instead of calculating the cosine */
+/* itself the difference from the value 1.0 is calculated, this can be done with */
+/* lower precision maths. */
+/* */
+/* 3. The value of the B2 coefficient is only calculated as a single precision value, */
+/* small errors in this value have a combined effect on the Q and Gain but not the */
+/* the frequency of the filter. */
+/* */
+/* 4. This function is entirely based on the LVEQNB_DoublePrecCoefs function */
+/* of the n bands equalizer (LVEQNB */
+/* */
+/****************************************************************************************/
+LVPSA_RETURN LVPSA_BPDoublePrecCoefs( LVM_UINT16 Fs,
+ LVPSA_FilterParam_t *pFilterParams,
+ BP_C32_Coefs_t *pCoefficients)
+{
+
+ extern LVM_INT16 LVPSA_TwoPiOnFsTable[];
+ extern LVM_INT16 LVPSA_DPCosCoef[];
+
+ /*
+ * Intermediate variables and temporary values
+ */
+ LVM_INT32 T0;
+ LVM_INT16 D;
+ LVM_INT32 A0;
+ LVM_INT32 B1;
+ LVM_INT32 B2;
+ LVM_INT32 Dt0;
+ LVM_INT32 B2_Den;
+ LVM_INT32 B2_Num;
+ LVM_INT32 CosErr;
+ LVM_INT16 coef;
+ LVM_INT32 factor;
+ LVM_INT16 t0;
+ LVM_INT16 i;
+
+ /*
+ * Get the filter definition
+ */
+ LVM_UINT16 Frequency = pFilterParams->CenterFrequency;
+ LVM_UINT16 QFactor = pFilterParams->QFactor;
+
+
+ /*
+ * Calculating the intermediate values
+ */
+ T0 = (LVM_INT32)Frequency * LVPSA_TwoPiOnFsTable[Fs]; /* T0 = 2 * Pi * Fc / Fs */
+ D = 3200; /* Floating point value 1.000000 (1*100*2^5) */
+ /* Force D = 1 : the function was originally used for a peaking filter.
+ The D parameter do not exist for a BandPass filter coefficients */
+
+ /*
+ * Calculate the B2 coefficient
+ */
+ Dt0 = D * (T0 >> 10);
+ B2_Den = (LVM_INT32)(((LVM_UINT32)QFactor << 19) + (LVM_UINT32)(Dt0 >> 2));
+ B2_Num = (LVM_INT32)((LVM_UINT32)(Dt0 >> 3) - ((LVM_UINT32)QFactor << 18));
+ B2 = (B2_Num / (B2_Den >> 16)) << 15;
+
+ /*
+ * Calculate the cosine error by a polynomial expansion using the equation:
+ *
+ * CosErr += coef(n) * t0^n For n = 0 to 4
+ */
+ T0 = (T0 >> 6) * 0x7f53; /* Scale to 1.0 in 16-bit for range 0 to fs/50 */
+ t0 = (LVM_INT16)(T0 >> 16);
+ factor = 0x7fff; /* Initialise to 1.0 for the a0 coefficient */
+ CosErr = 0; /* Initialise the error to zero */
+ for (i=1; i<5; i++)
+ {
+ coef = LVPSA_DPCosCoef[i]; /* Get the nth coefficient */
+ CosErr += (factor * coef) >> 5; /* The nth partial sum */
+ factor = (factor * t0) >> 15; /* Calculate t0^n */
+ }
+ CosErr = CosErr << (LVPSA_DPCosCoef[0]); /* Correct the scaling */
+
+ /*
+ * Calculate the B1 and A0 coefficients
+ */
+ B1 = (0x40000000 - B2); /* B1 = (0.5 - b2) */
+ A0 = ((B1 >> 16) * (CosErr >> 10)) >> 6; /* Temporary storage for (0.5 - b2) * coserr(t0) */
+ B1 -= A0; /* B1 = (0.5 - b2) * (1 - coserr(t0)) */
+ A0 = (0x40000000 + B2) >> 1; /* A0 = (0.5 + b2) / 2 */
+
+ /*
+ * Write coeff into the data structure
+ */
+ pCoefficients->A0 = A0;
+ pCoefficients->B1 = B1;
+ pCoefficients->B2 = B2;
+
+ return(LVPSA_OK);
+}
+
+/************************************************************************************/
+/* */
+/* FUNCTION: LVPSA_ClearFilterHistory */
+/* */
+/* DESCRIPTION: */
+/* Clears the filters' data history */
+/* */
+/* PARAMETERS: */
+/* pInst Pointer to the instance */
+/* */
+/* RETURNS: */
+/* LVPSA_OK Always succeeds */
+/* */
+/* NOTES: */
+/* */
+/************************************************************************************/
+LVPSA_RETURN LVPSA_ClearFilterHistory(LVPSA_InstancePr_t *pInst)
+{
+ LVM_INT8 *pTapAddress;
+ LVM_UINT32 i;
+
+ /* Band Pass filters taps */
+ pTapAddress = (LVM_INT8 *)pInst->pBP_Taps;
+ for(i = 0; i < pInst->nBands * sizeof(Biquad_1I_Order2_Taps_t); i++)
+ {
+ pTapAddress[i] = 0;
+ }
+
+ /* Quasi-peak filters taps */
+ pTapAddress = (LVM_INT8 *)pInst->pQPD_Taps;
+ for(i = 0; i < pInst->nBands * sizeof(QPD_Taps_t); i++)
+ {
+ pTapAddress[i] = 0;
+ }
+
+ return(LVPSA_OK);
+}
+
generated by cgit v1.1 at 2024-05-28 19:24:54 +0000