jamie@107: /* libxtract feature extraction library
jamie@107:  *  
jamie@107:  * Copyright (C) 2006 Jamie Bullock
jamie@107:  *
jamie@107:  * This program is free software; you can redistribute it and/or modify
jamie@107:  * it under the terms of the GNU General Public License as published by
jamie@107:  * the Free Software Foundation; either version 2 of the License, or
jamie@107:  * (at your option) any later version.
jamie@107:  *
jamie@107:  * This program is distributed in the hope that it will be useful,
jamie@107:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
jamie@107:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
jamie@107:  * GNU General Public License for more details.
jamie@107:  *
jamie@107:  * You should have received a copy of the GNU General Public License
jamie@107:  * along with this program; if not, write to the Free Software
jamie@107:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
jamie@107:  * USA.
jamie@107:  */
jamie@107: 
jamie@107: 
jamie@107: /* helper.c: helper functions. */
jamie@107: 
jamie@107: #include "xtract/libxtract.h"
jamie@107: 
jamie@107: int xtract_windowed(const float *data, const int N, const void *argv, float *result){
jamie@107: 
jamie@107:     int n;
jamie@107:     const float *window;
jamie@107: 
jamie@107:     n = N;
jamie@107:     window = (const float *)argv;
jamie@107: 
jamie@107:     while(n--)
jamie@107:         result[n] = data[n] * window[n];
jamie@107: 
jamie@107:     return XTRACT_SUCCESS;
jamie@107: 
jamie@107: }
jamie@107: 
jamie@107: int xtract_features_from_subframes(const float *data, const int N, const int feature, const void *argv, float *result){
jamie@107: 
jamie@107:     const float *frame1,
jamie@107:           *frame2;
jamie@107:     float *result1,
jamie@107:           *result2;
jamie@107: 
jamie@107:     int n,
jamie@107:         rv;
jamie@107: 
jamie@107:     n = N >> 1;
jamie@107: 
jamie@107:     frame1 = data;
jamie@107:     frame2 = data + n;
jamie@107:     result1 = result;
jamie@107:     result2 = result + n;
jamie@107: 
jamie@107:     rv = xtract[feature](frame1, n, argv, result1);
jamie@107: 
jamie@107:     if(rv == XTRACT_SUCCESS)
jamie@107:         rv = xtract[feature](frame2, n, argv, result2);
jamie@107: 
jamie@107:     return rv;
jamie@107: 
jamie@107: }