106 lines
3.8 KiB
C
106 lines
3.8 KiB
C
|
/*
|
||
|
|
==============================================================================
|
||
|
|
|
||
|
|
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.
|
||
|
|
|
||
|
|
The code included in this file is provided under the terms of the ISC license
|
||
|
|
http://www.isc.org/downloads/software-support-policy/isc-license. Permission
|
||
|
|
To use, copy, modify, and/or distribute this software for any purpose with or
|
||
|
|
without fee is hereby granted provided that the above copyright notice and
|
||
|
|
this permission notice appear in all copies.
|
||
|
|
|
||
|
|
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
|
||
|
|
{
|
||
|
|
|
||
|
|
//==============================================================================
|
||
|
|
/**
|
||
|
|
A type of AudioSource that takes an input source and changes its sample rate.
|
||
|
|
|
||
|
|
@see AudioSource, LagrangeInterpolator, CatmullRomInterpolator
|
||
|
|
|
||
|
|
@tags{Audio}
|
||
|
|
*/
|
||
|
|
class JUCE_API ResamplingAudioSource : public AudioSource
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
//==============================================================================
|
||
|
|
/** Creates a ResamplingAudioSource for a given input source.
|
||
|
|
|
||
|
|
@param inputSource the input source to read from
|
||
|
|
@param deleteInputWhenDeleted if true, the input source will be deleted when
|
||
|
|
this object is deleted
|
||
|
|
@param numChannels the number of channels to process
|
||
|
|
*/
|
||
|
|
ResamplingAudioSource (AudioSource* inputSource,
|
||
|
|
bool deleteInputWhenDeleted,
|
||
|
|
int numChannels = 2);
|
||
|
|
|
||
|
|
/** Destructor. */
|
||
|
|
~ResamplingAudioSource();
|
||
|
|
|
||
|
|
/** Changes the resampling ratio.
|
||
|
|
|
||
|
|
(This value can be changed at any time, even while the source is running).
|
||
|
|
|
||
|
|
@param samplesInPerOutputSample if set to 1.0, the input is passed through; higher
|
||
|
|
values will speed it up; lower values will slow it
|
||
|
|
down. The ratio must be greater than 0
|
||
|
|
*/
|
||
|
|
void setResamplingRatio (double samplesInPerOutputSample);
|
||
|
|
|
||
|
|
/** Returns the current resampling ratio.
|
||
|
|
|
||
|
|
This is the value that was set by setResamplingRatio().
|
||
|
|
*/
|
||
|
|
double getResamplingRatio() const noexcept { return ratio; }
|
||
|
|
|
||
|
|
/** Clears any buffers and filters that the resampler is using. */
|
||
|
|
void flushBuffers();
|
||
|
|
|
||
|
|
//==============================================================================
|
||
|
|
void prepareToPlay (int samplesPerBlockExpected, double sampleRate) override;
|
||
|
|
void releaseResources() override;
|
||
|
|
void getNextAudioBlock (const AudioSourceChannelInfo&) override;
|
||
|
|
|
||
|
|
private:
|
||
|
|
//==============================================================================
|
||
|
|
OptionalScopedPointer<AudioSource> input;
|
||
|
|
double ratio, lastRatio;
|
||
|
|
AudioBuffer<float> buffer;
|
||
|
|
int bufferPos, sampsInBuffer;
|
||
|
|
double subSampleOffset;
|
||
|
|
double coefficients[6];
|
||
|
|
SpinLock ratioLock;
|
||
|
|
const int numChannels;
|
||
|
|
HeapBlock<float*> destBuffers;
|
||
|
|
HeapBlock<const float*> srcBuffers;
|
||
|
|
|
||
|
|
void setFilterCoefficients (double c1, double c2, double c3, double c4, double c5, double c6);
|
||
|
|
void createLowPass (double proportionalRate);
|
||
|
|
|
||
|
|
struct FilterState
|
||
|
|
{
|
||
|
|
double x1, x2, y1, y2;
|
||
|
|
};
|
||
|
|
|
||
|
|
HeapBlock<FilterState> filterStates;
|
||
|
|
void resetFilters();
|
||
|
|
|
||
|
|
void applyFilter (float* samples, int num, FilterState& fs);
|
||
|
|
|
||
|
|
JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (ResamplingAudioSource)
|
||
|
|
};
|
||
|
|
|
||
|
|
} // namespace juce
|