Line data    Source code

       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
       6             :  * are met:
       7             :  *
       8             :  * 1.  Redistributions of source code must retain the above copyright
       9             :  *     notice, this list of conditions and the following disclaimer.
      10             :  * 2.  Redistributions in binary form must reproduce the above copyright
      11             :  *     notice, this list of conditions and the following disclaimer in the
      12             :  *     documentation and/or other materials provided with the distribution.
      13             :  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
      14             :  *     its contributors may be used to endorse or promote products derived
      15             :  *     from this software without specific prior written permission.
      16             :  *
      17             :  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
      18             :  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
      19             :  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
      20             :  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
      21             :  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
      22             :  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
      23             :  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
      24             :  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      25             :  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
      26             :  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
      27             :  */
      28             : 
      29             : #include "ReverbAccumulationBuffer.h"
      30             : #include "AudioNodeEngine.h"
      31             : #include "mozilla/PodOperations.h"
      32             : #include <algorithm>
      33             : 
      34             : using namespace mozilla;
      35             : 
      36             : namespace WebCore {
      37             : 
      38           0 : ReverbAccumulationBuffer::ReverbAccumulationBuffer(size_t length)
      39             :     : m_readIndex(0)
      40           0 :     , m_readTimeFrame(0)
      41             : {
      42           0 :   m_buffer.SetLength(length);
      43           0 :   PodZero(m_buffer.Elements(), length);
      44           0 : }
      45             : 
      46           0 : void ReverbAccumulationBuffer::readAndClear(float* destination, size_t numberOfFrames)
      47             : {
      48           0 :     size_t bufferLength = m_buffer.Length();
      49           0 :     bool isCopySafe = m_readIndex <= bufferLength && numberOfFrames <= bufferLength;
      50             : 
      51           0 :     MOZ_ASSERT(isCopySafe);
      52           0 :     if (!isCopySafe)
      53           0 :         return;
      54             : 
      55           0 :     size_t framesAvailable = bufferLength - m_readIndex;
      56           0 :     size_t numberOfFrames1 = std::min(numberOfFrames, framesAvailable);
      57           0 :     size_t numberOfFrames2 = numberOfFrames - numberOfFrames1;
      58             : 
      59           0 :     float* source = m_buffer.Elements();
      60           0 :     memcpy(destination, source + m_readIndex, sizeof(float) * numberOfFrames1);
      61           0 :     memset(source + m_readIndex, 0, sizeof(float) * numberOfFrames1);
      62             : 
      63             :     // Handle wrap-around if necessary
      64           0 :     if (numberOfFrames2 > 0) {
      65           0 :         memcpy(destination + numberOfFrames1, source, sizeof(float) * numberOfFrames2);
      66           0 :         memset(source, 0, sizeof(float) * numberOfFrames2);
      67             :     }
      68             : 
      69           0 :     m_readIndex = (m_readIndex + numberOfFrames) % bufferLength;
      70           0 :     m_readTimeFrame += numberOfFrames;
      71             : }
      72             : 
      73           0 : void ReverbAccumulationBuffer::updateReadIndex(int* readIndex, size_t numberOfFrames) const
      74             : {
      75             :     // Update caller's readIndex
      76           0 :     *readIndex = (*readIndex + numberOfFrames) % m_buffer.Length();
      77           0 : }
      78             : 
      79           0 : int ReverbAccumulationBuffer::accumulate(const float* source, size_t numberOfFrames, int* readIndex, size_t delayFrames)
      80             : {
      81           0 :     size_t bufferLength = m_buffer.Length();
      82             : 
      83           0 :     size_t writeIndex = (*readIndex + delayFrames) % bufferLength;
      84             : 
      85             :     // Update caller's readIndex
      86           0 :     *readIndex = (*readIndex + numberOfFrames) % bufferLength;
      87             : 
      88           0 :     size_t framesAvailable = bufferLength - writeIndex;
      89           0 :     size_t numberOfFrames1 = std::min(numberOfFrames, framesAvailable);
      90           0 :     size_t numberOfFrames2 = numberOfFrames - numberOfFrames1;
      91             : 
      92           0 :     float* destination = m_buffer.Elements();
      93             : 
      94           0 :     bool isSafe = writeIndex <= bufferLength && numberOfFrames1 + writeIndex <= bufferLength && numberOfFrames2 <= bufferLength;
      95           0 :     MOZ_ASSERT(isSafe);
      96           0 :     if (!isSafe)
      97           0 :         return 0;
      98             : 
      99           0 :     AudioBufferAddWithScale(source, 1.0f, destination + writeIndex, numberOfFrames1);
     100           0 :     if (numberOfFrames2 > 0) {
     101           0 :         AudioBufferAddWithScale(source + numberOfFrames1, 1.0f, destination, numberOfFrames2);
     102             :     }
     103             : 
     104           0 :     return writeIndex;
     105             : }
     106             : 
     107           0 : void ReverbAccumulationBuffer::reset()
     108             : {
     109           0 :     PodZero(m_buffer.Elements(), m_buffer.Length());
     110           0 :     m_readIndex = 0;
     111           0 :     m_readTimeFrame = 0;
     112           0 : }
     113             : 
     114             : } // namespace WebCore