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 * 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 ReverbConvolverStage_h 30 #define ReverbConvolverStage_h 31 32 #include "AudioArray.h" 33 #include "FFTFrame.h" 34 #include <wtf/OwnPtr.h> 35 36 namespace WebCore { 37 38 class ReverbAccumulationBuffer; 39 class ReverbConvolver; 40 class FFTConvolver; 41 42 // A ReverbConvolverStage represents the convolution associated with a sub-section of a large impulse response. 43 // It incorporates a delay line to account for the offset of the sub-section within the larger impulse response. 44 class ReverbConvolverStage { 45 public: 46 // renderPhase is useful to know so that we can manipulate the pre versus post delay so that stages will perform 47 // their heavy work (FFT processing) on different slices to balance the load in a real-time thread. 48 ReverbConvolverStage(float* impulseResponse, size_t responseLength, size_t reverbTotalLatency, size_t stageOffset, size_t stageLength, 49 size_t fftSize, size_t renderPhase, size_t renderSliceSize, ReverbAccumulationBuffer* accumulationBuffer); 50 51 // WARNING: framesToProcess must be such that it evenly divides the delay buffer size (stage_offset). 52 void process(float* source, size_t framesToProcess); 53 54 void processInBackground(ReverbConvolver* convolver, size_t framesToProcess); 55 56 void reset(); 57 58 // Useful for background processing 59 int inputReadIndex() const { return m_inputReadIndex; } 60 61 private: 62 FFTFrame m_fftKernel; 63 OwnPtr<FFTConvolver> m_convolver; 64 65 AudioFloatArray m_preDelayBuffer; 66 67 ReverbAccumulationBuffer* m_accumulationBuffer; 68 int m_accumulationReadIndex; 69 int m_inputReadIndex; 70 71 size_t m_preDelayLength; 72 size_t m_postDelayLength; 73 size_t m_preReadWriteIndex; 74 size_t m_framesProcessed; 75 76 AudioFloatArray m_temporaryBuffer; 77 78 size_t m_impulseResponseLength; 79 }; 80 81 } // namespace WebCore 82 83 #endif // ReverbConvolverStage_h 84
