/* SPDX-License-Identifier: BSD-3-Clause

*

* Copyright(c) 2022 Intel Corporation. All rights reserved.

*

* Author: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>

*/

/* Window functions related functions */

#ifndef __SOF_MATH_WINDOW_H__

#define __SOF_MATH_WINDOW_H__

#include <sof/audio/format.h>

#include <stdint.h>

#define WIN_BLACKMAN_A0 Q_CONVERT_FLOAT(7938.0 / 18608.0, 15) /* For "exact" blackman */

/**

* \brief Return rectangular window, simply values of one

* \param[in,out] win Output vector with coefficients

* \param[in] length Length of coefficients vector

*/

void win_rectangular_16b(int16_t win[], int length);

/**

* \brief Calculate Blackman window function, reference

* https://en.wikipedia.org/wiki/Window_function#Blackman_window

*

* \param[in,out] win Output vector with coefficients

* \param[in] length Length of coefficients vector

* \param[in] a0 Parameter for window shape, use e.g. 0.42 as Q1.15

*/

void win_blackman_16b(int16_t win[], int length, int16_t a0);

/**

* \brief Calculate Hamming window function, reference

* https://en.wikipedia.org/wiki/Window_function#Hann_and_Hamming_windows

*

* \param[in,out] win Output vector with coefficients

* \param[in] length Length of coefficients vector

*/

void win_hamming_16b(int16_t win[], int length);

/**

* \brief Calculate Povey window function. It's a window function

* from Pytorch.

*

* \param[in,out] win Output vector with coefficients

* \param[in] length Length of coefficients vector

*/

void win_povey_16b(int16_t win[], int length);

#endif /* __SOF_MATH_WINDOW_H__ */