paulxstretch/deps/juce/modules/juce_dsp/frequency/juce_Windowing.h

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/*
==============================================================================
This file is part of the JUCE library.
Copyright (c) 2020 - Raw Material Software Limited
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 6 End-User License
Agreement and JUCE Privacy Policy (both effective as of the 16th June 2020).
End User License Agreement: www.juce.com/juce-6-licence
Privacy Policy: www.juce.com/juce-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
{
/**
A class which provides multiple windowing functions useful for filter design
and spectrum analyzers.
The different functions provided here can be used by creating either a
WindowingFunction object, or a static function to fill an array with the
windowing method samples.
@tags{DSP}
*/
template <typename FloatType>
class JUCE_API WindowingFunction
{
public:
//==============================================================================
/** The windowing methods available. */
enum WindowingMethod
{
rectangular = 0,
triangular,
hann,
hamming,
blackman,
blackmanHarris,
flatTop,
kaiser,
numWindowingMethods
};
//==============================================================================
/** This constructor automatically fills a buffer of the specified size using
the fillWindowingTables function and the specified arguments.
@see fillWindowingTables
*/
WindowingFunction (size_t size, WindowingMethod,
bool normalise = true, FloatType beta = 0);
//==============================================================================
/** Fills the content of the object array with a given windowing method table.
@param size the size of the destination buffer allocated in the object
@param type the type of windowing method being used
@param normalise if the result must be normalised, creating a DC amplitude
response of one
@param beta an optional argument useful only for Kaiser's method
which must be positive and sets the properties of the
method (bandwidth and attenuation increases with beta)
*/
void fillWindowingTables (size_t size, WindowingMethod type,
bool normalise = true, FloatType beta = 0) noexcept;
/** Fills the content of an array with a given windowing method table.
@param samples the destination buffer pointer
@param size the size of the destination buffer allocated in the object
@param normalise if the result must be normalised, creating a DC amplitude
response of one
@param beta an optional argument useful only for Kaiser's method,
which must be positive and sets the properties of the
method (bandwidth and attenuation increases with beta)
*/
static void fillWindowingTables (FloatType* samples, size_t size, WindowingMethod,
bool normalise = true, FloatType beta = 0) noexcept;
/** Multiplies the content of a buffer with the given window. */
void multiplyWithWindowingTable (FloatType* samples, size_t size) noexcept;
/** Returns the name of a given windowing method. */
static const char* getWindowingMethodName (WindowingMethod) noexcept;
private:
//==============================================================================
Array<FloatType> windowTable;
JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (WindowingFunction)
};
} // namespace dsp
} // namespace juce