annotate src/dsp/SincWindow.cpp @ 196:da283326bcd3 tip master

Update plugin versions in RDF
author Chris Cannam <cannam@all-day-breakfast.com>
date Fri, 28 Feb 2020 09:43:02 +0000
parents a38d6940f8fb
children
rev   line source
c@119 1 /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
c@119 2 /*
c@119 3 Constant-Q library
c@119 4 Copyright (c) 2013-2014 Queen Mary, University of London
c@119 5
c@119 6 Permission is hereby granted, free of charge, to any person
c@119 7 obtaining a copy of this software and associated documentation
c@119 8 files (the "Software"), to deal in the Software without
c@119 9 restriction, including without limitation the rights to use, copy,
c@119 10 modify, merge, publish, distribute, sublicense, and/or sell copies
c@119 11 of the Software, and to permit persons to whom the Software is
c@119 12 furnished to do so, subject to the following conditions:
c@119 13
c@119 14 The above copyright notice and this permission notice shall be
c@119 15 included in all copies or substantial portions of the Software.
c@119 16
c@119 17 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
c@119 18 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
c@119 19 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
c@119 20 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
c@119 21 CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
c@119 22 CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
c@119 23 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
c@119 24
c@119 25 Except as contained in this notice, the names of the Centre for
c@119 26 Digital Music; Queen Mary, University of London; and Chris Cannam
c@119 27 shall not be used in advertising or otherwise to promote the sale,
c@119 28 use or other dealings in this Software without prior written
c@119 29 authorization.
c@119 30 */
c@119 31
c@119 32 #include "SincWindow.h"
c@119 33
c@119 34 #include <cmath>
c@119 35
c@119 36 void
c@119 37 SincWindow::init()
c@119 38 {
c@119 39 if (m_length < 1) {
c@119 40 return;
c@119 41 } else if (m_length < 2) {
c@119 42 m_window.push_back(1);
c@119 43 return;
c@119 44 } else {
c@119 45
c@119 46 int n0 = (m_length % 2 == 0 ? m_length/2 : (m_length - 1)/2);
c@119 47 int n1 = (m_length % 2 == 0 ? m_length/2 : (m_length + 1)/2);
c@119 48 double m = 2 * M_PI / m_p;
c@119 49
c@119 50 for (int i = 0; i < n0; ++i) {
c@119 51 double x = ((m_length / 2) - i) * m;
c@119 52 m_window.push_back(sin(x) / x);
c@119 53 }
c@119 54
c@119 55 m_window.push_back(1.0);
c@119 56
c@119 57 for (int i = 1; i < n1; ++i) {
c@119 58 double x = i * m;
c@119 59 m_window.push_back(sin(x) / x);
c@119 60 }
c@119 61 }
c@119 62 }
c@119 63