Support multiple HRTFDatabases for different sample-rates

Source/core/platform/audio/HRTFPanner.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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 29 matching lines @@
 
 namespace WebCore {
 
 // The value of 2 milliseconds is larger than the largest delay which exists in any HRTFKernel from the default HRTFDatabase (0.0136 seconds).
 // We ASSERT the delay values used in process() with this value.
 const double MaxDelayTimeSeconds = 0.002;
 
 const int UninitializedAzimuth = -1;
 const unsigned RenderingQuantum = 128;
 
-HRTFPanner::HRTFPanner(float sampleRate)
+HRTFPanner::HRTFPanner(float sampleRate, HRTFDatabase* database)
     : Panner(PanningModelHRTF)
+    , m_database(database)
     , m_sampleRate(sampleRate)
     , m_crossfadeSelection(CrossfadeSelection1)
     , m_azimuthIndex1(UninitializedAzimuth)
     , m_elevation1(0)
     , m_azimuthIndex2(UninitializedAzimuth)
     , m_elevation2(0)
     , m_crossfadeX(0)
     , m_crossfadeIncr(0)
     , m_convolverL1(fftSizeForSampleRate(sampleRate))
     , m_convolverR1(fftSizeForSampleRate(sampleRate))
     , m_convolverL2(fftSizeForSampleRate(sampleRate))
     , m_convolverR2(fftSizeForSampleRate(sampleRate))
     , m_delayLineL(MaxDelayTimeSeconds, sampleRate)
     , m_delayLineR(MaxDelayTimeSeconds, sampleRate)
     , m_tempL1(RenderingQuantum)
     , m_tempR1(RenderingQuantum)
     , m_tempL2(RenderingQuantum)
     , m_tempR2(RenderingQuantum)
 {
+    ASSERT(database);
 }
 
 HRTFPanner::~HRTFPanner()
 {
 }
 
 size_t HRTFPanner::fftSizeForSampleRate(float sampleRate)
 {
     // The HRTF impulse responses (loaded as audio resources) are 512 sample-frames @44.1KHz.
     // Currently, we truncate the impulse responses to half this size, but an FFT-size of twice impulse response size is needed (for convolution).
@@ skipping 12 matching lines @@
     m_delayLineR.reset();
 }
 
 int HRTFPanner::calculateDesiredAzimuthIndexAndBlend(double azimuth, double& azimuthBlend)
 {
     // Convert the azimuth angle from the range -180 -> +180 into the range 0 -> 360.
     // The azimuth index may then be calculated from this positive value.
     if (azimuth < 0)
         azimuth += 360.0;
 
-    HRTFDatabase* database = HRTFDatabaseLoader::defaultHRTFDatabase();
-    ASSERT(database);
-
-    int numberOfAzimuths = database->numberOfAzimuths();
+    int numberOfAzimuths = m_database->numberOfAzimuths();
     const double angleBetweenAzimuths = 360.0 / numberOfAzimuths;
 
     // Calculate the azimuth index and the blend (0 -> 1) for interpolation.
     double desiredAzimuthIndexFloat = azimuth / angleBetweenAzimuths;
     int desiredAzimuthIndex = static_cast<int>(desiredAzimuthIndexFloat);
     azimuthBlend = desiredAzimuthIndexFloat - static_cast<double>(desiredAzimuthIndex);
 
     // We don't immediately start using this azimuth index, but instead approach this index from the last index we rendered at.
     // This minimizes the clicks and graininess for moving sources which occur otherwise.
     desiredAzimuthIndex = max(0, desiredAzimuthIndex);
@@ skipping 10 matching lines @@
 
     bool isOutputGood = outputBus && outputBus->numberOfChannels() == 2 && framesToProcess <= outputBus->length();
     ASSERT(isOutputGood);
 
     if (!isInputGood || !isOutputGood) {
         if (outputBus)
             outputBus->zero();
         return;
     }
 
-    // This code only runs as long as the context is alive and after database has been loaded.
-    HRTFDatabase* database = HRTFDatabaseLoader::defaultHRTFDatabase();
-    ASSERT(database);
-    if (!database) {
-        outputBus->zero();
-        return;
-    }
-
     // IRCAM HRTF azimuths values from the loaded database is reversed from the panner's notion of azimuth.
     double azimuth = -desiredAzimuth;
 
     bool isAzimuthGood = azimuth >= -180.0 && azimuth <= 180.0;
     ASSERT(isAzimuthGood);
     if (!isAzimuthGood) {
         outputBus->zero();
         return;
     }
 
@@ skipping 54 matching lines @@
     for (unsigned segment = 0; segment < numberOfSegments; ++segment) {
         // Get the HRTFKernels and interpolated delays.
         HRTFKernel* kernelL1;
         HRTFKernel* kernelR1;
         HRTFKernel* kernelL2;
         HRTFKernel* kernelR2;
         double frameDelayL1;
         double frameDelayR1;
         double frameDelayL2;
         double frameDelayR2;
-        database->getKernelsFromAzimuthElevation(azimuthBlend, m_azimuthIndex1, m_elevation1, kernelL1, kernelR1, frameDelayL1, frameDelayR1);
-        database->getKernelsFromAzimuthElevation(azimuthBlend, m_azimuthIndex2, m_elevation2, kernelL2, kernelR2, frameDelayL2, frameDelayR2);
+        m_database->getKernelsFromAzimuthElevation(azimuthBlend, m_azimuthIndex1, m_elevation1, kernelL1, kernelR1, frameDelayL1, frameDelayR1);
+        m_database->getKernelsFromAzimuthElevation(azimuthBlend, m_azimuthIndex2, m_elevation2, kernelL2, kernelR2, frameDelayL2, frameDelayR2);
 
         bool areKernelsGood = kernelL1 && kernelR1 && kernelL2 && kernelR2;
         ASSERT(areKernelsGood);
         if (!areKernelsGood) {
             outputBus->zero();
             return;
         }
 
         ASSERT(frameDelayL1 / sampleRate() < MaxDelayTimeSeconds && frameDelayR1 / sampleRate() < MaxDelayTimeSeconds);
         ASSERT(frameDelayL2 / sampleRate() < MaxDelayTimeSeconds && frameDelayR2 / sampleRate() < MaxDelayTimeSeconds);
@@ skipping 74 matching lines @@
 double HRTFPanner::latencyTime() const
 {
     // The latency of a FFTConvolver is also fftSize() / 2, and is in addition to its tailTime of the
     // same value.
     return (fftSize() / 2) / static_cast<double>(sampleRate());
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)