content/media/webaudio/blink/FFTConvolver.h@97036ab72558 (annotated)
content/media/webaudio/blink/FFTConvolver.h
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* |
| michael@0 | 2 | * Copyright (C) 2010 Google Inc. All rights reserved. |
| michael@0 | 3 | * |
| michael@0 | 4 | * Redistribution and use in source and binary forms, with or without |
| michael@0 | 5 | * modification, are permitted provided that the following conditions |
| michael@0 | 6 | * are met: |
| michael@0 | 7 | * |
| michael@0 | 8 | * 1. Redistributions of source code must retain the above copyright |
| michael@0 | 9 | * notice, this list of conditions and the following disclaimer. |
| michael@0 | 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| michael@0 | 11 | * notice, this list of conditions and the following disclaimer in the |
| michael@0 | 12 | * documentation and/or other materials provided with the distribution. |
| michael@0 | 13 | * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of |
| michael@0 | 14 | * its contributors may be used to endorse or promote products derived |
| michael@0 | 15 | * from this software without specific prior written permission. |
| michael@0 | 16 | * |
| michael@0 | 17 | * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
| michael@0 | 18 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| michael@0 | 19 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| michael@0 | 20 | * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| michael@0 | 21 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| michael@0 | 22 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| michael@0 | 23 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| michael@0 | 24 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| michael@0 | 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| michael@0 | 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| michael@0 | 27 | */ |
| michael@0 | 28 | |
| michael@0 | 29 | #ifndef FFTConvolver_h |
| michael@0 | 30 | #define FFTConvolver_h |
| michael@0 | 31 | |
| michael@0 | 32 | #include "nsTArray.h" |
| michael@0 | 33 | #include "mozilla/FFTBlock.h" |
| michael@0 | 34 | #include "mozilla/MemoryReporting.h" |
| michael@0 | 35 | |
| michael@0 | 36 | namespace WebCore { |
| michael@0 | 37 | |
| michael@0 | 38 | typedef nsTArray<float> AudioFloatArray; |
| michael@0 | 39 | using mozilla::FFTBlock; |
| michael@0 | 40 | |
| michael@0 | 41 | class FFTConvolver { |
| michael@0 | 42 | public: |
| michael@0 | 43 | // fftSize must be a power of two |
| michael@0 | 44 | FFTConvolver(size_t fftSize); |
| michael@0 | 45 | |
| michael@0 | 46 | // |fftKernel| must be pre-scaled for FFTBlock::GetInverseWithoutScaling(). |
| michael@0 | 47 | // |
| michael@0 | 48 | // For now, with multiple calls to Process(), framesToProcess MUST add up EXACTLY to fftSize / 2 |
| michael@0 | 49 | // |
| michael@0 | 50 | // FIXME: Later, we can do more sophisticated buffering to relax this requirement... |
| michael@0 | 51 | // |
| michael@0 | 52 | // The input to output latency is equal to fftSize / 2 |
| michael@0 | 53 | // |
| michael@0 | 54 | // Processing in-place is allowed... |
| michael@0 | 55 | void process(FFTBlock* fftKernel, const float* sourceP, float* destP, size_t framesToProcess); |
| michael@0 | 56 | |
| michael@0 | 57 | void reset(); |
| michael@0 | 58 | |
| michael@0 | 59 | size_t fftSize() const { return m_frame.FFTSize(); } |
| michael@0 | 60 | |
| michael@0 | 61 | size_t sizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const; |
| michael@0 | 62 | size_t sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const; |
| michael@0 | 63 | |
| michael@0 | 64 | private: |
| michael@0 | 65 | FFTBlock m_frame; |
| michael@0 | 66 | |
| michael@0 | 67 | // Buffer input until we get fftSize / 2 samples then do an FFT |
| michael@0 | 68 | size_t m_readWriteIndex; |
| michael@0 | 69 | AudioFloatArray m_inputBuffer; |
| michael@0 | 70 | |
| michael@0 | 71 | // Stores output which we read a little at a time |
| michael@0 | 72 | AudioFloatArray m_outputBuffer; |
| michael@0 | 73 | |
| michael@0 | 74 | // Saves the 2nd half of the FFT buffer, so we can do an overlap-add with the 1st half of the next one |
| michael@0 | 75 | AudioFloatArray m_lastOverlapBuffer; |
| michael@0 | 76 | }; |
| michael@0 | 77 | |
| michael@0 | 78 | } // namespace WebCore |
| michael@0 | 79 | |
| michael@0 | 80 | #endif // FFTConvolver_h |
