third_party/WebKit/Source/platform/audio/AudioDSPKernelProcessor.cpp

   1 /*
   2  * Copyright (C) 2010 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
  15  * contributors may be used to endorse or promote products derived from
  16  * this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include "config.h"
  32
  33 #if ENABLE(WEB_AUDIO)
  34
  35 #include "platform/audio/AudioDSPKernelProcessor.h"
  36
  37 #include "platform/audio/AudioDSPKernel.h"
  38 #include "wtf/MainThread.h"
  39
  40 namespace blink {
  41
  42 // setNumberOfChannels() may later be called if the object is not yet in an "initialized" state.
  43 AudioDSPKernelProcessor::AudioDSPKernelProcessor(float sampleRate, unsigned numberOfChannels)
  44     : AudioProcessor(sampleRate, numberOfChannels)
  45     , m_hasJustReset(true)
  46 {
  47 }
  48
  49 void AudioDSPKernelProcessor::initialize()
  50 {
  51     if (isInitialized())
  52         return;
  53
  54     MutexLocker locker(m_processLock);
  55     ASSERT(!m_kernels.size());
  56
  57     // Create processing kernels, one per channel.
  58     for (unsigned i = 0; i < numberOfChannels(); ++i)
  59         m_kernels.append(createKernel());
  60
  61     m_initialized = true;
  62     m_hasJustReset = true;
  63 }
  64
  65 void AudioDSPKernelProcessor::uninitialize()
  66 {
  67     if (!isInitialized())
  68         return;
  69
  70     MutexLocker locker(m_processLock);
  71     m_kernels.clear();
  72
  73     m_initialized = false;
  74 }
  75
  76 void AudioDSPKernelProcessor::process(const AudioBus* source, AudioBus* destination, size_t framesToProcess)
  77 {
  78     ASSERT(source && destination);
  79     if (!source || !destination)
  80         return;
  81
  82     if (!isInitialized()) {
  83         destination->zero();
  84         return;
  85     }
  86
  87     MutexTryLocker tryLocker(m_processLock);
  88     if (tryLocker.locked()) {
  89         bool channelCountMatches = source->numberOfChannels() == destination->numberOfChannels() && source->numberOfChannels() == m_kernels.size();
  90         ASSERT(channelCountMatches);
  91         if (!channelCountMatches)
  92             return;
  93
  94         for (unsigned i = 0; i < m_kernels.size(); ++i)
  95             m_kernels[i]->process(source->channel(i)->data(), destination->channel(i)->mutableData(), framesToProcess);
  96     } else {
  97         // Unfortunately, the kernel is being processed by another thread.
  98         // See also ConvolverNode::process().
  99         destination->zero();
 100     }
 101 }
 102
 103 // Resets filter state
 104 void AudioDSPKernelProcessor::reset()
 105 {
 106     ASSERT(isMainThread());
 107     if (!isInitialized())
 108         return;
 109
 110     // Forces snap to parameter values - first time.
 111     // Any processing depending on this value must set it to false at the appropriate time.
 112     m_hasJustReset = true;
 113
 114     MutexLocker locker(m_processLock);
 115     for (unsigned i = 0; i < m_kernels.size(); ++i)
 116         m_kernels[i]->reset();
 117 }
 118
 119 void AudioDSPKernelProcessor::setNumberOfChannels(unsigned numberOfChannels)
 120 {
 121     if (numberOfChannels == m_numberOfChannels)
 122         return;
 123
 124     ASSERT(!isInitialized());
 125     if (!isInitialized())
 126         m_numberOfChannels = numberOfChannels;
 127 }
 128
 129 double AudioDSPKernelProcessor::tailTime() const
 130 {
 131     ASSERT(!isMainThread());
 132     MutexTryLocker tryLocker(m_processLock);
 133     if (tryLocker.locked()) {
 134         // It is expected that all the kernels have the same tailTime.
 135         return !m_kernels.isEmpty() ? m_kernels.first()->tailTime() : 0;
 136     }
 137     // Since we don't want to block the Audio Device thread, we return a large value
 138     // instead of trying to acquire the lock.
 139     return std::numeric_limits<double>::infinity();
 140 }
 141
 142 double AudioDSPKernelProcessor::latencyTime() const
 143 {
 144     ASSERT(!isMainThread());
 145     MutexTryLocker tryLocker(m_processLock);
 146     if (tryLocker.locked()) {
 147         // It is expected that all the kernels have the same latencyTime.
 148         return !m_kernels.isEmpty() ? m_kernels.first()->latencyTime() : 0;
 149     }
 150     // Since we don't want to block the Audio Device thread, we return a large value
 151     // instead of trying to acquire the lock.
 152     return std::numeric_limits<double>::infinity();
 153 }
 154
 155 } // namespace blink
 156
 157 #endif // ENABLE(WEB_AUDIO)