1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * CDDL HEADER START 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 7*0Sstevel@tonic-gate * with the License. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 11*0Sstevel@tonic-gate * See the License for the specific language governing permissions 12*0Sstevel@tonic-gate * and limitations under the License. 13*0Sstevel@tonic-gate * 14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 19*0Sstevel@tonic-gate * 20*0Sstevel@tonic-gate * CDDL HEADER END 21*0Sstevel@tonic-gate */ 22*0Sstevel@tonic-gate /* 23*0Sstevel@tonic-gate * Copyright (c) 1992-2001 by Sun Microsystems, Inc. 24*0Sstevel@tonic-gate * All rights reserved. 25*0Sstevel@tonic-gate */ 26*0Sstevel@tonic-gate 27*0Sstevel@tonic-gate #ifndef _MULTIMEDIA_FIR_H 28*0Sstevel@tonic-gate #define _MULTIMEDIA_FIR_H 29*0Sstevel@tonic-gate 30*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 31*0Sstevel@tonic-gate 32*0Sstevel@tonic-gate #ifdef __cplusplus 33*0Sstevel@tonic-gate extern "C" { 34*0Sstevel@tonic-gate #endif 35*0Sstevel@tonic-gate 36*0Sstevel@tonic-gate /* 37*0Sstevel@tonic-gate * Finite Impulse Response (FIR) filter object 38*0Sstevel@tonic-gate * 39*0Sstevel@tonic-gate * For every input sample, the FIR filter generates an output sample: 40*0Sstevel@tonic-gate * output = coef[0] * input + 41*0Sstevel@tonic-gate * coef[1] * state[order - 1] + 42*0Sstevel@tonic-gate * coef[2] * state[order - 2] + 43*0Sstevel@tonic-gate * ... 44*0Sstevel@tonic-gate * coef[order] * state[0] 45*0Sstevel@tonic-gate * 46*0Sstevel@tonic-gate * and the filter states are updated: 47*0Sstevel@tonic-gate * state[0] = state[1] 48*0Sstevel@tonic-gate * state[1] = state[2] 49*0Sstevel@tonic-gate * ... 50*0Sstevel@tonic-gate * state[order - 2] = state[order - 1] 51*0Sstevel@tonic-gate * state[order - 1] = input 52*0Sstevel@tonic-gate */ 53*0Sstevel@tonic-gate class Fir { 54*0Sstevel@tonic-gate protected: 55*0Sstevel@tonic-gate int order; // filter order, # taps = order + 1 56*0Sstevel@tonic-gate double *coef; // (order + 1) filter coeffs. 57*0Sstevel@tonic-gate double *state; // "order" filter states 58*0Sstevel@tonic-gate int delay; // actual delay between output & input 59*0Sstevel@tonic-gate 60*0Sstevel@tonic-gate virtual void updateState(double *data, int size); 61*0Sstevel@tonic-gate virtual void update_short(short *data, int size); 62*0Sstevel@tonic-gate virtual int flush(short *out); 63*0Sstevel@tonic-gate public: 64*0Sstevel@tonic-gate virtual void resetState(void); // reset states to zero 65*0Sstevel@tonic-gate Fir(void); 66*0Sstevel@tonic-gate Fir(int order_in); 67*0Sstevel@tonic-gate ~Fir(); 68*0Sstevel@tonic-gate virtual int getOrder(void); // get filter order value 69*0Sstevel@tonic-gate virtual int getNumCoefs(void); // get number of coefficients 70*0Sstevel@tonic-gate virtual void putCoef(double *coef_in); // put coef_in in filter coef 71*0Sstevel@tonic-gate virtual void getCoef(double *coef_out); // get filter coef 72*0Sstevel@tonic-gate // filter "size" input samples for "size" output samples 73*0Sstevel@tonic-gate virtual int filter_noadjust(short *in, int size, short *out); 74*0Sstevel@tonic-gate /* 75*0Sstevel@tonic-gate * filter "size" input samples. Output sample sequence is offset by 76*0Sstevel@tonic-gate * group delay samples to align with the input sample sequence. 77*0Sstevel@tonic-gate * the first call of this routine returns "size - group_delay" 78*0Sstevel@tonic-gate * output samples. Call this routine with size = 0 79*0Sstevel@tonic-gate * to fill the output buffer such that the total number of output 80*0Sstevel@tonic-gate * samples is equal to the number of input samples. 81*0Sstevel@tonic-gate */ 82*0Sstevel@tonic-gate virtual int getFlushSize(void); // size of out[] for the last call 83*0Sstevel@tonic-gate virtual int filter(short *in, int size, short *out); 84*0Sstevel@tonic-gate }; 85*0Sstevel@tonic-gate 86*0Sstevel@tonic-gate #ifdef __cplusplus 87*0Sstevel@tonic-gate } 88*0Sstevel@tonic-gate #endif 89*0Sstevel@tonic-gate 90*0Sstevel@tonic-gate #endif /* !_MULTIMEDIA_FIR_H */ 91