1 /* 2 * Copyright (C) 2010, 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 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY 17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 */ 24 25 #ifndef EqualPowerPanner_h 26 #define EqualPowerPanner_h 27 28 #include "core/platform/audio/Panner.h" 29 30 namespace WebCore { 31 32 // Common type of stereo panner as found in normal audio mixing equipment. 33 34 class EqualPowerPanner : public Panner { 35 public: 36 EqualPowerPanner(float sampleRate); 37 38 virtual void pan(double azimuth, double elevation, const AudioBus* inputBus, AudioBus* outputBuf, size_t framesToProcess); 39 40 virtual void reset() { m_isFirstRender = true; } 41 42 virtual double tailTime() const OVERRIDE { return 0; } 43 virtual double latencyTime() const OVERRIDE { return 0; } 44 45 private: 46 // For smoothing / de-zippering 47 bool m_isFirstRender; 48 double m_smoothingConstant; 49 50 double m_gainL; 51 double m_gainR; 52 }; 53 54 } // namespace WebCore 55 56 #endif // EqualPowerPanner_h 57
