| OLD | NEW |
| 1 /* | 1 /* |
| 2 * Copyright (C) 2012 Google Inc. All rights reserved. | 2 * Copyright (C) 2012 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 21 matching lines...) Expand all Loading... |
| 32 #include "platform/audio/AudioBus.h" | 32 #include "platform/audio/AudioBus.h" |
| 33 #include "wtf/Allocator.h" | 33 #include "wtf/Allocator.h" |
| 34 | 34 |
| 35 namespace blink { | 35 namespace blink { |
| 36 | 36 |
| 37 class AudioFIFO { | 37 class AudioFIFO { |
| 38 USING_FAST_MALLOC(AudioFIFO); | 38 USING_FAST_MALLOC(AudioFIFO); |
| 39 WTF_MAKE_NONCOPYABLE(AudioFIFO); | 39 WTF_MAKE_NONCOPYABLE(AudioFIFO); |
| 40 | 40 |
| 41 public: | 41 public: |
| 42 // Create a FIFO large enough to hold |fifoLength| frames of data of |numberOf
Channels| channels. | 42 // Create a FIFO large enough to hold |fifoLength| frames of data of |
| 43 // |numberOfChannels| channels. |
| 43 AudioFIFO(unsigned numberOfChannels, size_t fifoLength); | 44 AudioFIFO(unsigned numberOfChannels, size_t fifoLength); |
| 44 | 45 |
| 45 // Push the data from the bus into the FIFO. | 46 // Push the data from the bus into the FIFO. |
| 46 void push(const AudioBus*); | 47 void push(const AudioBus*); |
| 47 | 48 |
| 48 // Consume |framesToConsume| frames of data from the FIFO and put them in |des
tination|. The | 49 // Consume |framesToConsume| frames of data from the FIFO and put them in |
| 49 // corresponding frames are removed from the FIFO. | 50 // |destination|. The corresponding frames are removed from the FIFO. |
| 50 void consume(AudioBus* destination, size_t framesToConsume); | 51 void consume(AudioBus* destination, size_t framesToConsume); |
| 51 | 52 |
| 52 // Number of frames of data that are currently in the FIFO. | 53 // Number of frames of data that are currently in the FIFO. |
| 53 size_t framesInFifo() const { return m_framesInFifo; } | 54 size_t framesInFifo() const { return m_framesInFifo; } |
| 54 | 55 |
| 55 private: | 56 private: |
| 56 // Update the FIFO index by the step, with appropriate wrapping around the end
point. | 57 // Update the FIFO index by the step, with appropriate wrapping around the |
| 58 // endpoint. |
| 57 int updateIndex(int index, int step) { return (index + step) % m_fifoLength; } | 59 int updateIndex(int index, int step) { return (index + step) % m_fifoLength; } |
| 58 | 60 |
| 59 void findWrapLengths(size_t index, | 61 void findWrapLengths(size_t index, |
| 60 size_t providerSize, | 62 size_t providerSize, |
| 61 size_t& part1Length, | 63 size_t& part1Length, |
| 62 size_t& part2Length); | 64 size_t& part2Length); |
| 63 | 65 |
| 64 // The FIFO itself. In reality, the FIFO is a circular buffer. | 66 // The FIFO itself. In reality, the FIFO is a circular buffer. |
| 65 RefPtr<AudioBus> m_fifoAudioBus; | 67 RefPtr<AudioBus> m_fifoAudioBus; |
| 66 | 68 |
| 67 // The total available space in the FIFO. | 69 // The total available space in the FIFO. |
| 68 size_t m_fifoLength; | 70 size_t m_fifoLength; |
| 69 | 71 |
| 70 // The number of actual elements in the FIFO | 72 // The number of actual elements in the FIFO |
| 71 size_t m_framesInFifo; | 73 size_t m_framesInFifo; |
| 72 | 74 |
| 73 // Where to start reading from the FIFO. | 75 // Where to start reading from the FIFO. |
| 74 size_t m_readIndex; | 76 size_t m_readIndex; |
| 75 | 77 |
| 76 // Where to start writing to the FIFO. | 78 // Where to start writing to the FIFO. |
| 77 size_t m_writeIndex; | 79 size_t m_writeIndex; |
| 78 }; | 80 }; |
| 79 | 81 |
| 80 } // namespace blink | 82 } // namespace blink |
| 81 | 83 |
| 82 #endif // AudioFIFO.h | 84 #endif // AudioFIFO.h |
| OLD | NEW |