1/* 2 * Copyright (C) 2011 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29#ifndef ZeroPole_h 30#define ZeroPole_h 31 32#include "platform/PlatformExport.h" 33 34namespace WebCore { 35 36// ZeroPole is a simple filter with one zero and one pole. 37 38class PLATFORM_EXPORT ZeroPole { 39public: 40 ZeroPole() 41 : m_zero(0) 42 , m_pole(0) 43 , m_lastX(0) 44 , m_lastY(0) 45 { 46 } 47 48 void process(const float *source, float *destination, unsigned framesToProcess); 49 50 // Reset filter state. 51 void reset() { m_lastX = 0; m_lastY = 0; } 52 53 void setZero(float zero) { m_zero = zero; } 54 void setPole(float pole) { m_pole = pole; } 55 56 float zero() const { return m_zero; } 57 float pole() const { return m_pole; } 58 59private: 60 float m_zero; 61 float m_pole; 62 float m_lastX; 63 float m_lastY; 64}; 65 66} // namespace WebCore 67 68#endif // ZeroPole_h 69