/* -*- c++ -*- */
/*
 * Copyright 2012 Free Software Foundation, Inc.
 * 
 * This file is part of GNU Radio
 * 
 * GNU Radio 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 3, or (at your option)
 * any later version.
 * 
 * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifndef _GR_OPTFIR_H_
#define _GR_OPTFIR_H_

#include <gr_core_api.h>
#include <vector>
#include <cmath>

/*!
 * \brief Routines for designing optimal FIR filters.
 *
 * For a great intro to how all this stuff works, see section 6.6 of
 * "Digital Signal Processing: A Practical Approach", Emmanuael C. Ifeachor
 * and Barrie W. Jervis, Adison-Wesley, 1993.  ISBN 0-201-54413-X.
 * \ingroup filter_design
 */

class GR_CORE_API gr_optfir 
{
public:

	/*!
	* \brief Builds a low pass filter.
	*
	* \p gain:	Filter gain in the passband (linear)
	* \p Fs:	Sampling rate (sps)
	* \p freq1:	End of pass band (in Hz)
	* \p freq2:	Start of stop band (in Hz)
	* \p passband_ripple_db:	Pass band ripple in dB (should be small, < 1)
	* \p stopband_atten_db:	Stop band attenuation in dB (should be large, >= 60)
	* \p nextra_taps:	Extra taps to use in the filter (default=2)
	*/
	GR_CORE_API std::vector<double>
	low_pass (double gain,
		double Fs,
		double freq1,
		double freq2,
		double passband_ripple_db,
		double stopband_atten_db,
		int nextra_taps=2);

};

#endif