interpolateqLSP.c 1.91 KB
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/*
 interpolateqLSP.c

 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.
 */

#include "typedef.h"
#include "codecParameters.h"
#include "basicOperationsMacros.h"

/*****************************************************************************/
/* interpolateqLSP : interpolate previous and current qLSP according to      */
/*      spec. 3.2.5 : interpolated = (current+previous)/2                    */
/*    parameters:                                                            */
/*      -(i) previousqLSP : 10 values in Q0.15:  the qLSP of previous frame  */
/*      -(i) currentqLSP : 10 values in Q0.15: the qLSP of current frame     */
/*      -(o) interpolatedqLSP : 10 values in Q0.15 : the interpolated qLSP   */
/*                                                                           */
/*****************************************************************************/
void interpolateqLSP(word16_t previousqLSP[], word16_t currentqLSP[], word16_t interpolatedqLSP[])
{ /* interpolate previous and current qLSP according to spec. 3.2.5 : interpolated = (current+previous)/2 */
	int i;
	for (i=0; i<NB_LSP_COEFF; i++) {
		interpolatedqLSP[i] = (word16_t)PSHR(ADD32(previousqLSP[i], currentqLSP[i]),1);
	}
}