Split "Online" and "Offline" AudioContext processing

Source/platform/audio/ReverbConvolver.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 52 matching lines @@
     , m_inputBuffer(InputBufferSize)
     , m_minFFTSize(MinFFTSize) // First stage will have this size - successive stages will double in size each time
     , m_maxFFTSize(maxFFTSize) // until we hit m_maxFFTSize
 {
     // If we are using background threads then don't exceed this FFT size for the
     // stages which run in the real-time thread.  This avoids having only one or two
     // large stages (size 16384 or so) at the end which take a lot of time every several
     // processing slices.  This way we amortize the cost over more processing slices.
     m_maxRealtimeFFTSize = MaxRealtimeFFTSize;
 
-    // For the moment, a good way to know if we have real-time constraint is to check if we're using background threads.
-    // Otherwise, assume we're being run from a command-line tool.
-    bool hasRealtimeConstraint = useBackgroundThreads;
-
     const float* response = impulseResponse->data();
     size_t totalResponseLength = impulseResponse->length();
 
     // The total latency is zero because the direct-convolution is used in the leading portion.
     size_t reverbTotalLatency = 0;
 
     size_t stageOffset = 0;
     int i = 0;
     size_t fftSize = m_minFFTSize;
     while (stageOffset < totalResponseLength) {
@@ skipping 20 matching lines @@
             m_stages.append(stage.release());
 
         stageOffset += stageSize;
         ++i;
 
         if (!useDirectConvolver) {
             // Figure out next FFT size
             fftSize *= 2;
         }
 
-        if (hasRealtimeConstraint && !isBackgroundStage && fftSize > m_maxRealtimeFFTSize)
+        if (useBackgroundThreads && !isBackgroundStage && fftSize > m_maxRealtimeFFTSize)
             fftSize = m_maxRealtimeFFTSize;
         if (fftSize > m_maxFFTSize)
             fftSize = m_maxFFTSize;
     }
 
     // Start up background thread
     // FIXME: would be better to up the thread priority here.  It doesn't need to be real-time, but higher than the default...
     if (useBackgroundThreads && m_backgroundStages.size() > 0)
         m_backgroundThread = adoptPtr(Platform::current()->createThread("Reverb convolution background thread"));
 }
@@ skipping 65 matching lines @@
 }
 
 size_t ReverbConvolver::latencyFrames() const
 {
     return 0;
 }
 
 } // namespace blink
 
 #endif // ENABLE(WEB_AUDIO)