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 are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef AudioProcessor_h 32 #define AudioProcessor_h 33 34 #include "platform/PlatformExport.h" 35 #include "platform/heap/Handle.h" 36 37 namespace blink { 38 39 class AudioBus; 40 41 // AudioProcessor is an abstract base class representing an audio signal processing object with a single input and a single output, 42 // where the number of input channels equals the number of output channels. It can be used as one part of a complex DSP algorithm, 43 // or as the processor for a basic (one input - one output) AudioNode. 44 45 class PLATFORM_EXPORT AudioProcessor : public GarbageCollectedFinalized<AudioProcessor> { 46 public: 47 AudioProcessor(float sampleRate, unsigned numberOfChannels) 48 : m_initialized(false) 49 , m_numberOfChannels(numberOfChannels) 50 , m_sampleRate(sampleRate) 51 { 52 } 53 54 virtual ~AudioProcessor(); 55 virtual void trace(Visitor*); 56 57 // Full initialization can be done here instead of in the constructor. 58 virtual void initialize() = 0; 59 virtual void uninitialize() = 0; 60 61 // Processes the source to destination bus. The number of channels must match in source and destination. 62 virtual void process(const AudioBus* source, AudioBus* destination, size_t framesToProcess) = 0; 63 64 // Resets filter state 65 virtual void reset() = 0; 66 67 virtual void setNumberOfChannels(unsigned) = 0; 68 virtual unsigned numberOfChannels() const = 0; 69 70 bool isInitialized() const { return m_initialized; } 71 72 float sampleRate() const { return m_sampleRate; } 73 74 virtual double tailTime() const = 0; 75 virtual double latencyTime() const = 0; 76 77 protected: 78 bool m_initialized; 79 unsigned m_numberOfChannels; 80 float m_sampleRate; 81 }; 82 83 } // namespace blink 84 85 #endif // AudioProcessor_h 86
