1/*
2 * Copyright (C) 2010 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1.  Redistributions of source code must retain the above copyright
9 *     notice, this list of conditions and the following disclaimer.
10 * 2.  Redistributions in binary form must reproduce the above copyright
11 *     notice, this list of conditions and the following disclaimer in the
12 *     documentation and/or other materials provided with the distribution.
13 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 *     its contributors may be used to endorse or promote products derived
15 *     from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef FFTFrame_h
30#define FFTFrame_h
31
32#include "platform/PlatformExport.h"
33#include "platform/audio/AudioArray.h"
34#include "wtf/Forward.h"
35#include "wtf/PassOwnPtr.h"
36#include "wtf/Threading.h"
37
38#if OS(MACOSX)
39#include <Accelerate/Accelerate.h>
40#elif USE(WEBAUDIO_OPENMAX_DL_FFT)
41#include <dl/sp/api/omxSP.h>
42#elif USE(WEBAUDIO_FFMPEG)
43struct RDFTContext;
44#elif USE(WEBAUDIO_IPP)
45#include <ipps.h>
46#endif
47
48namespace blink {
49
50// Defines the interface for an "FFT frame", an object which is able to perform a forward
51// and reverse FFT, internally storing the resultant frequency-domain data.
52
53class PLATFORM_EXPORT FFTFrame {
54public:
55    // The constructors, destructor, and methods up to the CROSS-PLATFORM section have platform-dependent implementations.
56
57    FFTFrame(unsigned fftSize);
58    FFTFrame(); // creates a blank/empty frame for later use with createInterpolatedFrame()
59    FFTFrame(const FFTFrame& frame);
60    ~FFTFrame();
61
62    static void initialize();
63    static void cleanup();
64    void doFFT(const float* data);
65    void doInverseFFT(float* data);
66
67    float* realData() const { return const_cast<float*>(m_realData.data()); }
68    float* imagData() const { return const_cast<float*>(m_imagData.data()); }
69
70    unsigned fftSize() const { return m_FFTSize; }
71    unsigned log2FFTSize() const { return m_log2FFTSize; }
72
73    // CROSS-PLATFORM
74    // The remaining public methods have cross-platform implementations:
75
76    // Interpolates from frame1 -> frame2 as x goes from 0.0 -> 1.0
77    static PassOwnPtr<FFTFrame> createInterpolatedFrame(const FFTFrame& frame1, const FFTFrame& frame2, double x);
78    void doPaddedFFT(const float* data, size_t dataSize); // zero-padding with dataSize <= fftSize
79    double extractAverageGroupDelay();
80    void addConstantGroupDelay(double sampleFrameDelay);
81    void multiply(const FFTFrame&); // multiplies ourself with frame : effectively operator*=()
82
83#ifndef NDEBUG
84    void print(); // for debugging
85#endif
86
87private:
88    void interpolateFrequencyComponents(const FFTFrame& frame1, const FFTFrame& frame2, double x);
89
90    unsigned m_FFTSize;
91    unsigned m_log2FFTSize;
92    AudioFloatArray m_realData;
93    AudioFloatArray m_imagData;
94
95#if OS(MACOSX)
96    DSPSplitComplex& dspSplitComplex() { return m_frame; }
97    DSPSplitComplex dspSplitComplex() const { return m_frame; }
98    static FFTSetup fftSetupForSize(unsigned fftSize);
99    static FFTSetup* fftSetups;
100    FFTSetup m_FFTSetup;
101    DSPSplitComplex m_frame;
102#elif USE(WEBAUDIO_FFMPEG)
103    static RDFTContext* contextForSize(unsigned fftSize, int trans);
104    RDFTContext* m_forwardContext;
105    RDFTContext* m_inverseContext;
106    float* getUpToDateComplexData();
107    AudioFloatArray m_complexData;
108#elif USE(WEBAUDIO_IPP)
109    Ipp8u* m_buffer;
110    IppsDFTSpec_R_32f* m_DFTSpec;
111    float* getUpToDateComplexData();
112    AudioFloatArray m_complexData;
113#elif USE(WEBAUDIO_OPENMAX_DL_FFT)
114    static OMXFFTSpec_R_F32* contextForSize(unsigned log2FFTSize);
115    OMXFFTSpec_R_F32* m_forwardContext;
116    OMXFFTSpec_R_F32* m_inverseContext;
117    AudioFloatArray m_complexData;
118#endif
119};
120
121} // namespace blink
122
123#endif // FFTFrame_h
124