sync with upstream

1 files changed, 39 insertions, 0 deletions

diff --git a/xbmc/utils/rfft.h b/xbmc/utils/rfft.h
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+/*
+ *  Copyright (C) 2015-2018 Team Kodi
+ *  This file is part of Kodi - https://kodi.tv
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ *  See LICENSES/README.md for more information.
+ */
+
+#pragma once
+
+#include "contrib/kissfft/kiss_fftr.h"
+
+#include <vector>
+
+//! \brief Class performing a RFFT of interleaved stereo data.
+class RFFT
+{
+public:
+  //! \brief The constructor creates a RFFT plan.
+  //! \brief size Length of time data for a single channel.
+  //! \brief windowed Whether or not to apply a Hann window to data.
+  RFFT(int size, bool windowed=false);
+
+  //! \brief Free the RFFT plan
+  ~RFFT();
+
+  //! \brief Calculate FFTs
+  //! \param input Input data of size 2*m_size
+  //! \param output Output data of size m_size.
+  void calc(const float* input, float* output);
+protected:
+  //! \brief Apply a Hann window to a buffer.
+  //! \param data Vector with data to apply window to.
+  static void hann(std::vector<kiss_fft_scalar>& data);
+
+  size_t m_size;       //!< Size for a single channel.
+  bool m_windowed;     //!< Whether or not a Hann window is applied.
+  kiss_fftr_cfg m_cfg; //!< FFT plan
+};