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Diffstat (limited to 'extern/audaspace/include/fx/FFTConvolver.h')
| -rw-r--r-- | extern/audaspace/include/fx/FFTConvolver.h | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/extern/audaspace/include/fx/FFTConvolver.h b/extern/audaspace/include/fx/FFTConvolver.h new file mode 100644 index 00000000000..62ce1cbf5ad --- /dev/null +++ b/extern/audaspace/include/fx/FFTConvolver.h @@ -0,0 +1,196 @@ +/******************************************************************************* +* Copyright 2015-2016 Juan Francisco Crespo Galán +* +* Licensed under the Apache License, Version 2.0 (the "License"); +* you may not use this file except in compliance with the License. +* You may obtain a copy of the License at +* +* http://www.apache.org/licenses/LICENSE-2.0 +* +* Unless required by applicable law or agreed to in writing, software +* distributed under the License is distributed on an "AS IS" BASIS, +* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +* See the License for the specific language governing permissions and +* limitations under the License. +******************************************************************************/ + +#pragma once + +/** +* @file FFTConvolver.h +* @ingroup fx +* The FFTConvolver class. +*/ + +#include "IReader.h" +#include "ISound.h" +#include "util/FFTPlan.h" + +#include <memory> +#include <vector> + +AUD_NAMESPACE_BEGIN +/** +* This class allows to easily convolve a sound using the Fourier transform. +*/ +class AUD_API FFTConvolver +{ +private: + /** + * A shared pointer to an FFT plan. + */ + std::shared_ptr<FFTPlan> m_plan; + + /** + * The FFT size, must be at least M+L-1. + */ + int m_N; + + /** + * The length of the impulse response. + */ + int m_M; + + /** + * The max length of the input slices. + */ + int m_L; + + /** + * The real length of the internal buffer in fftwf_complex elements. + */ + int m_realBufLen; + + /** + * The internal buffer for the FFTS. + */ + std::complex<sample_t>* m_inBuffer; + + /** + * A shift buffer for the FDL method + */ + sample_t* m_shiftBuffer; + + /** + * A buffer to store the extra data obtained after each partial convolution. + */ + float* m_tail; + + /** + * The provided impulse response. + */ + std::shared_ptr<std::vector<std::complex<sample_t>>> m_irBuffer; + + /** + * If the tail is being read, this marks the current position. + */ + int m_tailPos; + + // delete copy constructor and operator= + FFTConvolver(const FFTConvolver&) = delete; + FFTConvolver& operator=(const FFTConvolver&) = delete; + +public: + /** + * Creates a new FFTConvolver. + * \param ir A shared pointer to a vector with the impulse response data in the frequency domain (see ImpulseResponse class for an easy way to obtain it). + * \param plan A shared pointer to and FFT plan. + */ + FFTConvolver(std::shared_ptr<std::vector<std::complex<sample_t>>> ir, std::shared_ptr<FFTPlan> plan); + virtual ~FFTConvolver(); + + /** + * Convolves the data that is provided with the inpulse response. + * \param[in] inBuffer A buffer with the input data to be convolved. + * \param[in] outBuffer A pointer to the buffer in which the convolution result will be written. + * \param[in,out] length The number of samples to be convolved (the length of both the inBuffer and the outBuffer). + * The convolution output should be larger than the input, but since this class uses the overlap + * add method, the extra length will be saved internally. + * It must be equal or lower than N/2 (N=size of the FFTPlan) or the call will fail, setting this variable to 0 since no data would be + * written in the outBuffer. + */ + void getNext(const sample_t* inBuffer, sample_t* outBuffer, int& length); + + /** + * Convolves the data that is provided with the inpulse response. + * \param[in] inBuffer A buffer with the input data to be convolved. + * \param[in] outBuffer A pointer to the buffer in which the convolution result will be written. + * \param[in,out] length The number of samples to be convolved (the length of both the inBuffer and the outBuffer). + * The convolution output should be larger than the input, but since this class uses the overlap + * add method, the extra length will be saved internally. + * It must be equal or lower than N/2 (N=size of the FFTPlan) or the call will fail, setting this variable to 0 since no data would be + * written in the outBuffer. + * \param[in] transformedData A pointer to a buffer in which the Fourier transform of the input will be written. + */ + void getNext(const sample_t* inBuffer, sample_t* outBuffer, int& length, fftwf_complex* transformedData); + + /** + * Convolves the data that is provided with the inpulse response. + * \param[in] inBuffer A buffer with the input data to be convolved. Its length must be N/2 + 1 + * \param[in] outBuffer A pointer to the buffer in which the convolution result will be written. + * \param[in,out] length The number of samples to be convolved and the length of the outBuffer. + * The convolution output should be larger than the input, but since this class uses the overlap + * add method, the extra length will be saved internally. + * It must be equal or lower than N/2 (N=size of the FFTPlan) or the call will fail and set the value of length to 0 since no data would be + * written in the outBuffer. + */ + void getNext(const fftwf_complex* inBuffer, sample_t* outBuffer, int& length); + + /** + * Gets the internally stored extra data which is result of the convolution. + * \param[in,out] length The count of samples that should be read. Shall + * contain the real count of samples after reading, in case + * there were only fewer samples available. + * A smaller value also indicates the end of the data. + * \param[out] eos End of stream, whether the end is reached or not. + * \param[in] buffer The pointer to the buffer to read into. + */ + void getTail(int& length, bool& eos, sample_t* buffer); + + /** + * Resets the internally stored data so a new convolution can be started. + */ + void clear(); + + /** + * Calculates the Inverse Fast Fourier Transform of the input array. + * \param[in] inBuffer A buffer with the input data to be transformed. Its length must be N/2 + 1 + * \param[in] outBuffer A pointer to the buffer in which the transform result will be written. + * \param[in,out] length The number of samples to be transformed and the length of the outBuffer. + * It must be equal or lower than N, but tipically N/2 should be used (N=size of the FFTPlan) or the call will fail and the value + * of length will be setted to 0, since no data would be written in the outBuffer. + */ + void IFFT_FDL(const fftwf_complex* inBuffer, sample_t* outBuffer, int& length); + + /** + * Multiplicates a frequency domain input by the impulse response and accumulates the result to a buffer. + * \param[in] inBuffer A buffer of complex numbers, samples in the frequency domain, that will be multiplied by the impulse response. Its length must be N/2 + 1 + * \param[in] accBuffer A pointer to the buffer into which the result of the multiplication will be summed. Its length must be N/2 + 1 + */ + void getNextFDL(const std::complex<sample_t>* inBuffer, std::complex<sample_t>* accBuffer); + + /** + * Transforms an input array of real data to the frequency domain and multiplies it by the impulse response. The result is accumulated to a buffer. + * \param[in] inBuffer A buffer of real numbers, samples in the time domain, that will be multiplied by the impulse response. + * \param[in] accBuffer A pointer to the buffer into which the result of the multiplication will be summed. Its length must be N/2 + 1. + * \param[in,out] length The number of samples to be transformed and the length of the inBuffer. + * It must be equal or lower than N/2 (N=size of the FFTPlan) or the call will fail and the value + * of length will be setted to 0, since no data would be written in the outBuffer. + * \param[in] transformedData A pointer to a buffer in which the Fourier transform of the input will be written. + */ + void getNextFDL(const sample_t* inBuffer, std::complex<sample_t>* accBuffer, int& length, fftwf_complex* transformedData); + + /** + * Changes the impulse response and resets the FFTConvolver. + * \param ir A shared pointer to a vector with the data of the impulse response in the frequency domain. + */ + void setImpulseResponse(std::shared_ptr<std::vector<std::complex<sample_t>>> ir); + + /** + * Retrieves the current impulse response being used. + * \return The current impulse response. + */ + std::shared_ptr<std::vector<std::complex<sample_t>>> getImpulseResponse(); +}; + +AUD_NAMESPACE_END |