12c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* 22c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * Copyright (C) 2004-2010 NXP Software 32c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * Copyright (C) 2010 The Android Open Source Project 42c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * 52c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * Licensed under the Apache License, Version 2.0 (the "License"); 62c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * you may not use this file except in compliance with the License. 72c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * You may obtain a copy of the License at 82c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * 92c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * http://www.apache.org/licenses/LICENSE-2.0 102c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * 112c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * Unless required by applicable law or agreed to in writing, software 122c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * distributed under the License is distributed on an "AS IS" BASIS, 132c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 142c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * See the License for the specific language governing permissions and 152c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent * limitations under the License. 162c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent */ 172c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent 182c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/*-------------------------------------------------------------------------*/ 192c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent#include "BIQUAD.h" 202c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent#include "BP_1I_D16F32Cll_TRC_WRA_01_Private.h" 212c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent 222c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent 232c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/*-------------------------------------------------------------------------*/ 242c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* FUNCTION: */ 252c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* BP_1I_D16F32Cll_TRC_WRA_01_Init */ 262c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* */ 272c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* DESCRIPTION: */ 282c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* These functions initializes a Band pass filter (BIQUAD) */ 292c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* biquadratic Filter Sections. */ 302c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* */ 312c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* PARAMETERS: */ 322c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* pInstance - output, returns the pointer to the State Variable */ 332c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* This state pointer must be passed to any subsequent */ 342c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* call to "Biquad" functions. */ 352c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* pTaps - input, pointer to the taps memory */ 362c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* pCoef - input, pointer to the coefficient structure */ 372c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* N - M coefficient factor of QM.N */ 382c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* */ 392c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* The coefficients are modified in the init() function such that lower */ 402c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* half word is right shifted by one and most significant bit of the lower */ 412c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* word is made to be zero. */ 422c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* */ 432c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* Reason: For MIPS effciency,we are using DSP 32*16 multiplication */ 442c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* instruction. But we have 32*32 multiplication. This can be realized by two 32*16 */ 452c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* multiplication. But 16th bit in the 32 bit word is not a sign bit. So this is done */ 462c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* by putting 16th bit to zero and lossing one bit precision by division of lower */ 472c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* half word by 2. */ 482c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* RETURNS: */ 492c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* void return code */ 502c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/*-------------------------------------------------------------------------*/ 512c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurentvoid BP_1I_D16F32Cll_TRC_WRA_01_Init ( Biquad_Instance_t *pInstance, 522c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent Biquad_1I_Order2_Taps_t *pTaps, 532c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent BP_C32_Coefs_t *pCoef) 542c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent{ 552c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent PFilter_State pBiquadState = (PFilter_State) pInstance; 562c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent pBiquadState->pDelays =(LVM_INT32 *) pTaps; 572c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent 582c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent pBiquadState->coefs[0] = pCoef->A0; 592c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent pBiquadState->coefs[1] = pCoef->B2; 602c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent pBiquadState->coefs[2] = pCoef->B1; 612c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent} 622c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/*-------------------------------------------------------------------------*/ 632c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent/* End Of File: BP_1I_D16F32Cll_TRC_WRA_01_Init.c */ 642c8e5cab3faa6d360e222b7a6c40a80083d021acEric Laurent 65