| /* |
| * Copyright (C) 2011 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of |
| * its contributors may be used to endorse or promote products derived |
| * from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #ifndef DynamicsCompressor_h |
| #define DynamicsCompressor_h |
| |
| #include "platform/audio/AudioArray.h" |
| #include "platform/audio/DynamicsCompressorKernel.h" |
| #include "platform/audio/ZeroPole.h" |
| #include "wtf/Allocator.h" |
| #include "wtf/Noncopyable.h" |
| #include <memory> |
| |
| namespace blink { |
| |
| class AudioBus; |
| |
| // DynamicsCompressor implements a flexible audio dynamics compression effect |
| // such as is commonly used in musical production and game audio. It lowers the |
| // volume of the loudest parts of the signal and raises the volume of the |
| // softest parts, making the sound richer, fuller, and more controlled. |
| |
| class PLATFORM_EXPORT DynamicsCompressor { |
| USING_FAST_MALLOC(DynamicsCompressor); |
| WTF_MAKE_NONCOPYABLE(DynamicsCompressor); |
| |
| public: |
| enum { |
| ParamThreshold, |
| ParamKnee, |
| ParamRatio, |
| ParamAttack, |
| ParamRelease, |
| ParamPreDelay, |
| ParamReleaseZone1, |
| ParamReleaseZone2, |
| ParamReleaseZone3, |
| ParamReleaseZone4, |
| ParamPostGain, |
| ParamFilterStageGain, |
| ParamFilterStageRatio, |
| ParamFilterAnchor, |
| ParamEffectBlend, |
| ParamReduction, |
| ParamLast |
| }; |
| |
| DynamicsCompressor(float sampleRate, unsigned numberOfChannels); |
| |
| void process(const AudioBus* sourceBus, |
| AudioBus* destinationBus, |
| unsigned framesToProcess); |
| void reset(); |
| void setNumberOfChannels(unsigned); |
| |
| void setParameterValue(unsigned parameterID, float value); |
| float parameterValue(unsigned parameterID); |
| |
| float sampleRate() const { return m_sampleRate; } |
| float nyquist() const { return m_sampleRate / 2; } |
| |
| double tailTime() const { return 0; } |
| double latencyTime() const { |
| return m_compressor.latencyFrames() / static_cast<double>(sampleRate()); |
| } |
| |
| protected: |
| unsigned m_numberOfChannels; |
| |
| // m_parameters holds the tweakable compressor parameters. |
| float m_parameters[ParamLast]; |
| void initializeParameters(); |
| |
| float m_sampleRate; |
| |
| // Emphasis filter controls. |
| float m_lastFilterStageRatio; |
| float m_lastAnchor; |
| float m_lastFilterStageGain; |
| |
| std::unique_ptr<const float* []> m_sourceChannels; |
| std::unique_ptr<float* []> m_destinationChannels; |
| |
| // The core compressor. |
| DynamicsCompressorKernel m_compressor; |
| }; |
| |
| } // namespace blink |
| |
| #endif // DynamicsCompressor_h |