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: /* xtract_window_private.h: declares window generation functions */
jamie@107: 
jamie@107: #define PI 3.1415926535897931
jamie@107: 
jamie@107: /** \brief generate a Gaussian window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  * \param sd the standard deviation of the "distribution" represented by the Gaussian curve. The higher the value of sd, the wider the curve. Generally sd <= 0.5
jamie@107:  *
jamie@107:  */
jamie@107: void gauss(float *window, const int N, const float sd);
jamie@107: 
jamie@107: /** \brief generate a Hamming window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  *
jamie@107:  */
jamie@107: void hamming(float *window, const int N);
jamie@107: 
jamie@107: /** \brief generate a Hann window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  *
jamie@107:  */
jamie@107: void hann(float *window, const int N);
jamie@107: 
jamie@107: /** \brief generate a Bartlett window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  *
jamie@107:  */
jamie@107: void bartlett(float *window, const int N);
jamie@107: 
jamie@107: /** \brief generate a Triangular window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  *
jamie@107:  */
jamie@107: void triangular(float *window, const int N);
jamie@107: 
jamie@107: /** \brief generate a Bartlett-Hann  window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  *
jamie@107:  */
jamie@107: void bartlett_hann(float *window, const int N);
jamie@107: 
jamie@107: /** \brief generate a Blackman window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  *
jamie@107:  */
jamie@107: void blackman(float *window, const int N);
jamie@107: 
jamie@107: /** \brief generate a Kaiser window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  * \param alpha The larger the value of |alpha|, the narrower the window becomes
jamie@107:  *
jamie@107:  */
jamie@107: void kaiser(float *window, const int N, const float alpha);
jamie@107: 
jamie@107: /** \brief generate a Blackman-Harris window
jamie@107:  *
jamie@107:  * \param *window a pointer to an array to contain the window data
jamie@107:  * \param N the number of elements in the array pointed to by *window
jamie@107:  *
jamie@107:  */
jamie@107: void blackman_harris(float *window, const int N);
jamie@107: