spandsp: filter_tools.h Source File

spandsp 0.0.6

filter_tools.h
1/*
2 * SpanDSP - a series of DSP components for telephony
3 *
4 * filter_tools.h - A collection of routines used for filter design.
5 *
6 * Written by Steve Underwood <steveu@coppice.org>
7 *
8 * Copyright (C) 2008 Steve Underwood
9 *
10 * Based on:
11 * mkshape -- design raised cosine FIR filter
12 * A.J. Fisher, University of York <fisher@minster.york.ac.uk>, November 1996
13 *
14 * All rights reserved.
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU Lesser General Public License version 2.1,
18 * as published by the Free Software Foundation.
19 *
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU Lesser General Public License for more details.
24 *
25 * You should have received a copy of the GNU Lesser General Public
26 * License along with this program; if not, write to the Free Software
27 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28 */
29
30#if !defined(_FILTER_TOOLS_H_)
31#define _FILTER_TOOLS_H_
32
33#if defined(__cplusplus)
34extern "C"
35{
36#endif
37
38void ifft(complex_t data[], int len);
39void apply_hamming_window(double coeffs[], int len);
40void truncate_coeffs(double coeffs[], int len, int bits, int hilbert);
41
42void compute_raised_cosine_filter(double coeffs[],
43 int len,
44 int root,
45 int sinc_compensate,
46 double alpha,
47 double beta);
48
49void compute_hilbert_transform(double coeffs[], int len);
50
51
52#if defined(__cplusplus)
53}
54#endif
55
56#endif
57/*- End of file ------------------------------------------------------------*/
complex_t
Definition complex.h:54