content/media/webaudio/blink/ReverbAccumulationBuffer.cpp@44a2da4a2ab2 (annotated)
content/media/webaudio/blink/ReverbAccumulationBuffer.cpp
Fri, 16 Jan 2015 04:50:19 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Fri, 16 Jan 2015 04:50:19 +0100
- branch
- TOR_BUG_9701
- changeset 13
- 44a2da4a2ab2
- permissions
- -rw-r--r--
Replace accessor implementation with direct member state manipulation, by
request https://trac.torproject.org/projects/tor/ticket/9701#comment:32
| 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 | #include "ReverbAccumulationBuffer.h" |
| michael@0 | 30 | #include "AudioNodeEngine.h" |
| michael@0 | 31 | #include "mozilla/PodOperations.h" |
| michael@0 | 32 | #include <algorithm> |
| michael@0 | 33 | |
| michael@0 | 34 | using namespace mozilla; |
| michael@0 | 35 | |
| michael@0 | 36 | namespace WebCore { |
| michael@0 | 37 | |
| michael@0 | 38 | ReverbAccumulationBuffer::ReverbAccumulationBuffer(size_t length) |
| michael@0 | 39 | : m_readIndex(0) |
| michael@0 | 40 | , m_readTimeFrame(0) |
| michael@0 | 41 | { |
| michael@0 | 42 | m_buffer.SetLength(length); |
| michael@0 | 43 | PodZero(m_buffer.Elements(), length); |
| michael@0 | 44 | } |
| michael@0 | 45 | |
| michael@0 | 46 | void ReverbAccumulationBuffer::readAndClear(float* destination, size_t numberOfFrames) |
| michael@0 | 47 | { |
| michael@0 | 48 | size_t bufferLength = m_buffer.Length(); |
| michael@0 | 49 | bool isCopySafe = m_readIndex <= bufferLength && numberOfFrames <= bufferLength; |
| michael@0 | 50 | |
| michael@0 | 51 | MOZ_ASSERT(isCopySafe); |
| michael@0 | 52 | if (!isCopySafe) |
| michael@0 | 53 | return; |
| michael@0 | 54 | |
| michael@0 | 55 | size_t framesAvailable = bufferLength - m_readIndex; |
| michael@0 | 56 | size_t numberOfFrames1 = std::min(numberOfFrames, framesAvailable); |
| michael@0 | 57 | size_t numberOfFrames2 = numberOfFrames - numberOfFrames1; |
| michael@0 | 58 | |
| michael@0 | 59 | float* source = m_buffer.Elements(); |
| michael@0 | 60 | memcpy(destination, source + m_readIndex, sizeof(float) * numberOfFrames1); |
| michael@0 | 61 | memset(source + m_readIndex, 0, sizeof(float) * numberOfFrames1); |
| michael@0 | 62 | |
| michael@0 | 63 | // Handle wrap-around if necessary |
| michael@0 | 64 | if (numberOfFrames2 > 0) { |
| michael@0 | 65 | memcpy(destination + numberOfFrames1, source, sizeof(float) * numberOfFrames2); |
| michael@0 | 66 | memset(source, 0, sizeof(float) * numberOfFrames2); |
| michael@0 | 67 | } |
| michael@0 | 68 | |
| michael@0 | 69 | m_readIndex = (m_readIndex + numberOfFrames) % bufferLength; |
| michael@0 | 70 | m_readTimeFrame += numberOfFrames; |
| michael@0 | 71 | } |
| michael@0 | 72 | |
| michael@0 | 73 | void ReverbAccumulationBuffer::updateReadIndex(int* readIndex, size_t numberOfFrames) const |
| michael@0 | 74 | { |
| michael@0 | 75 | // Update caller's readIndex |
| michael@0 | 76 | *readIndex = (*readIndex + numberOfFrames) % m_buffer.Length(); |
| michael@0 | 77 | } |
| michael@0 | 78 | |
| michael@0 | 79 | int ReverbAccumulationBuffer::accumulate(float* source, size_t numberOfFrames, int* readIndex, size_t delayFrames) |
| michael@0 | 80 | { |
| michael@0 | 81 | size_t bufferLength = m_buffer.Length(); |
| michael@0 | 82 | |
| michael@0 | 83 | size_t writeIndex = (*readIndex + delayFrames) % bufferLength; |
| michael@0 | 84 | |
| michael@0 | 85 | // Update caller's readIndex |
| michael@0 | 86 | *readIndex = (*readIndex + numberOfFrames) % bufferLength; |
| michael@0 | 87 | |
| michael@0 | 88 | size_t framesAvailable = bufferLength - writeIndex; |
| michael@0 | 89 | size_t numberOfFrames1 = std::min(numberOfFrames, framesAvailable); |
| michael@0 | 90 | size_t numberOfFrames2 = numberOfFrames - numberOfFrames1; |
| michael@0 | 91 | |
| michael@0 | 92 | float* destination = m_buffer.Elements(); |
| michael@0 | 93 | |
| michael@0 | 94 | bool isSafe = writeIndex <= bufferLength && numberOfFrames1 + writeIndex <= bufferLength && numberOfFrames2 <= bufferLength; |
| michael@0 | 95 | MOZ_ASSERT(isSafe); |
| michael@0 | 96 | if (!isSafe) |
| michael@0 | 97 | return 0; |
| michael@0 | 98 | |
| michael@0 | 99 | AudioBufferAddWithScale(source, 1.0f, destination + writeIndex, numberOfFrames1); |
| michael@0 | 100 | |
| michael@0 | 101 | // Handle wrap-around if necessary |
| michael@0 | 102 | if (numberOfFrames2 > 0) { |
| michael@0 | 103 | AudioBufferAddWithScale(source + numberOfFrames1, 1.0f, destination, numberOfFrames2); |
| michael@0 | 104 | } |
| michael@0 | 105 | |
| michael@0 | 106 | return writeIndex; |
| michael@0 | 107 | } |
| michael@0 | 108 | |
| michael@0 | 109 | void ReverbAccumulationBuffer::reset() |
| michael@0 | 110 | { |
| michael@0 | 111 | PodZero(m_buffer.Elements(), m_buffer.Length()); |
| michael@0 | 112 | m_readIndex = 0; |
| michael@0 | 113 | m_readTimeFrame = 0; |
| michael@0 | 114 | } |
| michael@0 | 115 | |
| michael@0 | 116 | } // namespace WebCore |
