1 /* Libvisual-plugins - Standard plugins for libvisual 2 * 3 * Copyright (C) 2004, 2005, 2006 Antti Silvast <asilvast@iki.fi> 4 * 5 * Authors: Antti Silvast <asilvast@iki.fi> 6 * Dennis Smit <ds@nerds-incorporated.org> 7 * 8 * $Id: notch.h,v 1.3 2006/01/22 13:25:26 synap Exp $ 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as 12 * published by the Free Software Foundation; either version 2 13 * of the License, or (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 23 */ 24 25 typedef struct { 26 float cutoff; 27 float a0; 28 float b1; 29 float b2; 30 float x1; 31 float x2; 32 } NOTCH_FILTER; 33 34 #define SAMPLING_RATE 44100 35 36 NOTCH_FILTER * init_notch(float cutoff); 37 float process_notch(NOTCH_FILTER * l, float x0); 38