1/* Copyright (C) 2013 Google Inc. All rights reserved.
2 *
3 * Redistribution and use in source and binary forms, with or without
4 * modification, are permitted provided that the following conditions
5 * are met:
6 *
7 * 1.  Redistributions of source code must retain the above copyright
8 *     notice, this list of conditions and the following disclaimer.
9 * 2.  Redistributions in binary form must reproduce the above copyright
10 *     notice, this list of conditions and the following disclaimer in the
11 *     documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
20 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25#include "config.h"
26
27#if ENABLE(WEB_AUDIO)
28
29#if OS(ANDROID) && USE(WEBAUDIO_OPENMAX_DL_FFT)
30
31#include "platform/audio/FFTFrame.h"
32
33#include "platform/audio/AudioArray.h"
34#include "wtf/MathExtras.h"
35#include <dl/sp/api/armSP.h>
36#include <dl/sp/api/omxSP.h>
37
38namespace blink {
39
40#if ENABLE(ASSERT)
41const unsigned kMaxFFTPow2Size = 15;
42#endif
43
44// Normal constructor: allocates for a given fftSize.
45FFTFrame::FFTFrame(unsigned fftSize)
46    : m_FFTSize(fftSize)
47    , m_log2FFTSize(static_cast<unsigned>(log2(fftSize)))
48    , m_realData(fftSize / 2)
49    , m_imagData(fftSize / 2)
50    , m_forwardContext(0)
51    , m_inverseContext(0)
52    , m_complexData(fftSize)
53{
54    // We only allow power of two.
55    ASSERT(1UL << m_log2FFTSize == m_FFTSize);
56
57    m_forwardContext = contextForSize(m_log2FFTSize);
58    m_inverseContext = contextForSize(m_log2FFTSize);
59}
60
61// Creates a blank/empty frame (interpolate() must later be called).
62FFTFrame::FFTFrame()
63    : m_FFTSize(0)
64    , m_log2FFTSize(0)
65    , m_forwardContext(0)
66    , m_inverseContext(0)
67{
68}
69
70// Copy constructor.
71FFTFrame::FFTFrame(const FFTFrame& frame)
72    : m_FFTSize(frame.m_FFTSize)
73    , m_log2FFTSize(frame.m_log2FFTSize)
74    , m_realData(frame.m_FFTSize / 2)
75    , m_imagData(frame.m_FFTSize / 2)
76    , m_forwardContext(0)
77    , m_inverseContext(0)
78    , m_complexData(frame.m_FFTSize)
79{
80    m_forwardContext = contextForSize(m_log2FFTSize);
81    m_inverseContext = contextForSize(m_log2FFTSize);
82
83    // Copy/setup frame data.
84    unsigned nbytes = sizeof(float) * (m_FFTSize / 2);
85    memcpy(realData(), frame.realData(), nbytes);
86    memcpy(imagData(), frame.imagData(), nbytes);
87}
88
89void FFTFrame::initialize()
90{
91}
92
93void FFTFrame::cleanup()
94{
95}
96
97FFTFrame::~FFTFrame()
98{
99    if (m_forwardContext)
100        free(m_forwardContext);
101    if (m_inverseContext)
102        free(m_inverseContext);
103}
104
105void FFTFrame::doFFT(const float* data)
106{
107    ASSERT(m_forwardContext);
108
109    if (m_forwardContext) {
110        AudioFloatArray complexFFT(m_FFTSize + 2);
111
112        omxSP_FFTFwd_RToCCS_F32(data, complexFFT.data(), m_forwardContext);
113
114        unsigned len = m_FFTSize / 2;
115
116        // Split FFT data into real and imaginary arrays.
117        const float* c = complexFFT.data();
118        float* real = m_realData.data();
119        float* imag = m_imagData.data();
120        for (unsigned k = 1; k < len; ++k) {
121            int index = 2 * k;
122            real[k] = c[index];
123            imag[k] = c[index + 1];
124        }
125        real[0] = c[0];
126        imag[0] = c[m_FFTSize];
127    }
128}
129
130void FFTFrame::doInverseFFT(float* data)
131{
132    ASSERT(m_inverseContext);
133
134    if (m_inverseContext) {
135        AudioFloatArray fftDataArray(m_FFTSize + 2);
136
137        unsigned len = m_FFTSize / 2;
138
139        // Pack the real and imaginary data into the complex array format
140        float* fftData = fftDataArray.data();
141        const float* real = m_realData.data();
142        const float* imag = m_imagData.data();
143        for (unsigned k = 1; k < len; ++k) {
144            int index = 2 * k;
145            fftData[index] = real[k];
146            fftData[index + 1] = imag[k];
147        }
148        fftData[0] = real[0];
149        fftData[1] = 0;
150        fftData[m_FFTSize] = imag[0];
151        fftData[m_FFTSize + 1] = 0;
152
153        omxSP_FFTInv_CCSToR_F32(fftData, data, m_inverseContext);
154    }
155}
156
157OMXFFTSpec_R_F32* FFTFrame::contextForSize(unsigned log2FFTSize)
158{
159    ASSERT(log2FFTSize);
160    ASSERT(log2FFTSize <= kMaxFFTPow2Size);
161    int bufSize;
162    OMXResult status = omxSP_FFTGetBufSize_R_F32(log2FFTSize, &bufSize);
163
164    if (status == OMX_Sts_NoErr) {
165        OMXFFTSpec_R_F32* context = static_cast<OMXFFTSpec_R_F32*>(malloc(bufSize));
166        omxSP_FFTInit_R_F32(context, log2FFTSize);
167        return context;
168    }
169
170    return 0;
171}
172
173} // namespace blink
174
175#endif // #if OS(ANDROID) && !USE(WEBAUDIO_OPENMAX_DL_FFT)
176
177#endif // ENABLE(WEB_AUDIO)
178