/* preProcessing.h Copyright (C) 2011 Belledonne Communications, Grenoble, France Author : Johan Pascal This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifndef PREPROCESSING_H #define PREPROCESSING_H /* internal variable initialisations */ void initPreProcessing(bcg729EncoderChannelContextStruct *encoderChannelContext); /*****************************************************************************/ /* preProcessing : 2nd order highpass filter with cut off frequency at 140Hz */ /* Algorithm: */ /* y[i] = BO*x[i] + B1*x[i-1] + B2*x[i-2] + A1*y[i-1] + A2*y[i-2] */ /* parameters : */ /* -(i/o) encoderChannelContext : the channel context data */ /* -(i) signal : 80 values in Q0 */ /* -(o) preProcessedSignal : 80 values in Q0 */ /* */ /*****************************************************************************/ void preProcessing(bcg729EncoderChannelContextStruct *encoderChannelContext, word16_t signal[], word16_t preProcessedSignal[]); #endif /* ifndef PREPROCESSING_H */