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29 #include "AudioUtilities.h"
30 #include <wtf/MathExtras.h>
34 namespace AudioUtilities {
36 double decibelsToLinear(double decibels)
38 return pow(10.0, 0.05 * decibels);
41 double linearToDecibels(double linear)
43 // It's not possible to calculate decibels for a zero linear value since it would be -Inf.
44 // -1000.0 dB represents a very tiny linear value in case we ever reach this case.
49 return 20.0 * log10(linear);
52 double discreteTimeConstantForSampleRate(double timeConstant, double sampleRate)
54 // hardcoded value is temporary build fix for Windows.
55 // FIXME: replace hardcode 2.718282 with M_E until the correct MathExtras.h solution is determined.
56 return 1.0 - pow(1.0 / 2.718282, 1.0 / (sampleRate * timeConstant));
63 #endif // ENABLE(WEB_AUDIO)