/* ============================================================================== This file is part of the JUCE library. Copyright (c) 2017 - ROLI Ltd. JUCE is an open source library subject to commercial or open-source licensing. By using JUCE, you agree to the terms of both the JUCE 5 End-User License Agreement and JUCE 5 Privacy Policy (both updated and effective as of the 27th April 2017). End User License Agreement: www.juce.com/juce-5-licence Privacy Policy: www.juce.com/juce-5-privacy-policy Or: You may also use this code under the terms of the GPL v3 (see www.gnu.org/licenses). JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE DISCLAIMED. ============================================================================== */ namespace juce { namespace dsp { /** Performs stereo uniform-partitioned convolution of an input signal with an impulse response in the frequency domain, using the juce FFT class. It provides some thread-safe functions to load impulse responses as well, from audio files or memory on the fly without any noticeable artefacts, performing resampling and trimming if necessary. The processing is equivalent to the time domain convolution done in the class FIRFilter, with a FIRFilter::Coefficients object having as coefficients the samples of the impulse response. However, it is more efficient in general to do frequency domain convolution when the size of the impulse response is higher than 64 samples. @see FIRFilter, FIRFilter::Coefficients, FFT @tags{DSP} */ class JUCE_API Convolution { public: //============================================================================== /** Initialises an object for performing convolution in the frequency domain. */ Convolution(); /** Destructor. */ ~Convolution(); //============================================================================== /** Must be called before loading any impulse response, to provide to the convolution the maximumBufferSize to handle, and the sample rate useful for optional resampling. */ void prepare (const ProcessSpec&); /** Resets the processing pipeline, ready to start a new stream of data. */ void reset() noexcept; /** Performs the filter operation on the given set of samples, with optional stereo processing. */ template void process (const ProcessContext& context) noexcept { static_assert (std::is_same::value, "Convolution engine only supports single precision floating point data"); processSamples (context.getInputBlock(), context.getOutputBlock(), context.isBypassed); } //============================================================================== /** This function loads an impulse response audio file from memory, added in a JUCE project with the Projucer as binary data. It can load any of the audio formats registered in JUCE, and performs some resampling and pre-processing as well if needed. Note : obviously, don't try to use this function on float samples, since the data is supposed to be an audio file in its binary format, and be sure that the original data is not going to move at all its memory location during the process !! @param sourceData the block of data to use as the stream's source @param sourceDataSize the number of bytes in the source data block @param wantsStereo requests to process both stereo channels or only one mono channel @param wantsTrimming requests to trim the start and the end of the impulse response @param size the expected size for the impulse response after loading, can be set to 0 for requesting maximum original impulse response size @param wantsNormalization requests to normalize the impulse response amplitude */ void loadImpulseResponse (const void* sourceData, size_t sourceDataSize, bool wantsStereo, bool wantsTrimming, size_t size, bool wantsNormalization = true); /** This function loads an impulse response from an audio file on any drive. It can load any of the audio formats registered in JUCE, and performs some resampling and pre-processing as well if needed. @param fileImpulseResponse the location of the audio file @param wantsStereo requests to process both stereo channels or only one mono channel @param wantsTrimming requests to trim the start and the end of the impulse response @param size the expected size for the impulse response after loading, can be set to 0 for requesting maximum original impulse response size @param wantsNormalization requests to normalize the impulse response amplitude */ void loadImpulseResponse (const File& fileImpulseResponse, bool wantsStereo, bool wantsTrimming, size_t size, bool wantsNormalization = true); /** This function loads an impulse response from an audio buffer, which is copied before doing anything else. Performs some resampling and pre-processing as well if needed. @param buffer the AudioBuffer to use @param bufferSampleRate the sampleRate of the data in the AudioBuffer @param wantsStereo requests to process both stereo channels or only one mono channel @param wantsTrimming requests to trim the start and the end of the impulse response @param wantsNormalization requests to normalize the impulse response amplitude @param size the expected size for the impulse response after loading, can be set to 0 for requesting maximum original impulse response size */ void copyAndLoadImpulseResponseFromBuffer (AudioBuffer& buffer, double bufferSampleRate, bool wantsStereo, bool wantsTrimming, bool wantsNormalization, size_t size); /** This function loads an impulse response from an audio block, which is copied before doing anything else. Performs some resampling and pre-processing as well if needed. @param block the AudioBlock to use @param bufferSampleRate the sampleRate of the data in the AudioBuffer @param wantsStereo requests to process both stereo channels or only one channel @param wantsTrimming requests to trim the start and the end of the impulse response @param wantsNormalization requests to normalize the impulse response amplitude @param size the expected size for the impulse response after loading, -1 for maximum length */ void copyAndLoadImpulseResponseFromBlock (AudioBlock block, double bufferSampleRate, bool wantsStereo, bool wantsTrimming, bool wantsNormalization, size_t size); private: //============================================================================== struct Pimpl; std::unique_ptr pimpl; //============================================================================== void processSamples (const AudioBlock&, AudioBlock&, bool isBypassed) noexcept; //============================================================================== double sampleRate; bool currentIsBypassed = false; bool isActive = false; LinearSmoothedValue volumeDry[2], volumeWet[2]; AudioBlock dryBuffer; HeapBlock dryBufferStorage; //============================================================================== JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (Convolution) }; } // namespace dsp } // namespace juce