OLD | NEW |
1 /* | 1 /* |
2 * Copyright (C) 2011 Google Inc. All rights reserved. | 2 * Copyright (C) 2011 Google Inc. All rights reserved. |
3 * | 3 * |
4 * Redistribution and use in source and binary forms, with or without | 4 * Redistribution and use in source and binary forms, with or without |
5 * modification, are permitted provided that the following conditions | 5 * modification, are permitted provided that the following conditions |
6 * are met: | 6 * are met: |
7 * | 7 * |
8 * 1. Redistributions of source code must retain the above copyright | 8 * 1. Redistributions of source code must retain the above copyright |
9 * notice, this list of conditions and the following disclaimer. | 9 * notice, this list of conditions and the following disclaimer. |
10 * 2. Redistributions in binary form must reproduce the above copyright | 10 * 2. Redistributions in binary form must reproduce the above copyright |
(...skipping 24 matching lines...) Expand all Loading... |
35 #include "platform/audio/VectorMath.h" | 35 #include "platform/audio/VectorMath.h" |
36 | 36 |
37 extern "C" { | 37 extern "C" { |
38 #include <libavcodec/avfft.h> | 38 #include <libavcodec/avfft.h> |
39 } | 39 } |
40 | 40 |
41 #include "platform/wtf/MathExtras.h" | 41 #include "platform/wtf/MathExtras.h" |
42 | 42 |
43 namespace blink { | 43 namespace blink { |
44 | 44 |
45 #if DCHECK_IS_ON() | |
46 // Max FFT size for FFMPEG. WebAudio currently only uses FFTs up to size 15 | 45 // Max FFT size for FFMPEG. WebAudio currently only uses FFTs up to size 15 |
47 // (2^15 points). | 46 // (2^15 points). |
48 const int kMaxFFTPow2Size = 16; | 47 const int kMaxFFTPow2Size = 16; |
49 #endif | |
50 | 48 |
51 // Normal constructor: allocates for a given fftSize. | 49 // Normal constructor: allocates for a given fftSize. |
52 FFTFrame::FFTFrame(unsigned fftSize) | 50 FFTFrame::FFTFrame(unsigned fftSize) |
53 : m_FFTSize(fftSize), | 51 : m_FFTSize(fftSize), |
54 m_log2FFTSize(static_cast<unsigned>(log2(fftSize))), | 52 m_log2FFTSize(static_cast<unsigned>(log2(fftSize))), |
55 m_realData(fftSize / 2), | 53 m_realData(fftSize / 2), |
56 m_imagData(fftSize / 2), | 54 m_imagData(fftSize / 2), |
57 m_forwardContext(nullptr), | 55 m_forwardContext(nullptr), |
58 m_inverseContext(nullptr), | 56 m_inverseContext(nullptr), |
59 m_complexData(fftSize) { | 57 m_complexData(fftSize) { |
60 // We only allow power of two. | 58 // We only allow power of two. |
61 ASSERT(1UL << m_log2FFTSize == m_FFTSize); | 59 DCHECK_EQ(1UL << m_log2FFTSize, m_FFTSize); |
62 | 60 |
63 m_forwardContext = contextForSize(fftSize, DFT_R2C); | 61 m_forwardContext = contextForSize(fftSize, DFT_R2C); |
64 m_inverseContext = contextForSize(fftSize, IDFT_C2R); | 62 m_inverseContext = contextForSize(fftSize, IDFT_C2R); |
65 } | 63 } |
66 | 64 |
67 // Creates a blank/empty frame (interpolate() must later be called). | 65 // Creates a blank/empty frame (interpolate() must later be called). |
68 FFTFrame::FFTFrame() | 66 FFTFrame::FFTFrame() |
69 : m_FFTSize(0), | 67 : m_FFTSize(0), |
70 m_log2FFTSize(0), | 68 m_log2FFTSize(0), |
71 m_forwardContext(nullptr), | 69 m_forwardContext(nullptr), |
(...skipping 78 matching lines...) Expand 10 before | Expand all | Expand 10 after Loading... |
150 return const_cast<float*>(m_complexData.data()); | 148 return const_cast<float*>(m_complexData.data()); |
151 } | 149 } |
152 | 150 |
153 RDFTContext* FFTFrame::contextForSize(unsigned fftSize, int trans) { | 151 RDFTContext* FFTFrame::contextForSize(unsigned fftSize, int trans) { |
154 // FIXME: This is non-optimal. Ideally, we'd like to share the contexts for | 152 // FIXME: This is non-optimal. Ideally, we'd like to share the contexts for |
155 // FFTFrames of the same size. But FFmpeg's RDFT uses a scratch buffer | 153 // FFTFrames of the same size. But FFmpeg's RDFT uses a scratch buffer |
156 // inside the context and so they are not thread-safe. We could improve this | 154 // inside the context and so they are not thread-safe. We could improve this |
157 // by sharing the FFTFrames on a per-thread basis. | 155 // by sharing the FFTFrames on a per-thread basis. |
158 DCHECK(fftSize); | 156 DCHECK(fftSize); |
159 int pow2size = static_cast<int>(log2(fftSize)); | 157 int pow2size = static_cast<int>(log2(fftSize)); |
160 ASSERT(pow2size < kMaxFFTPow2Size); | 158 DCHECK_LT(pow2size, kMaxFFTPow2Size); |
161 | 159 |
162 RDFTContext* context = av_rdft_init(pow2size, (RDFTransformType)trans); | 160 RDFTContext* context = av_rdft_init(pow2size, (RDFTransformType)trans); |
163 return context; | 161 return context; |
164 } | 162 } |
165 | 163 |
166 } // namespace blink | 164 } // namespace blink |
167 | 165 |
168 #endif // USE(WEBAUDIO_FFMPEG) | 166 #endif // USE(WEBAUDIO_FFMPEG) |
OLD | NEW |