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#ifndef HRTFElevation_h
#define HRTFElevation_h
#include "platform/audio/HRTFKernel.h"
#include "wtf/Noncopyable.h"
#include "wtf/OwnPtr.h"
#include "wtf/PassOwnPtr.h"
#include "wtf/PassRefPtr.h"
#include "wtf/RefCounted.h"
#include "wtf/RefPtr.h"
#include "wtf/text/CString.h"
#include "wtf/text/WTFString.h"
namespace WebCore {
// HRTFElevation contains all of the HRTFKernels (one left ear and one right ear per azimuth angle) for a particular elevation.
class PLATFORM_EXPORT HRTFElevation {
WTF_MAKE_NONCOPYABLE(HRTFElevation);
public:
// Loads and returns an HRTFElevation with the given HRTF database subject name and elevation from browser (or WebKit.framework) resources.
// Normally, there will only be a single HRTF database set, but this API supports the possibility of multiple ones with different names.
// Interpolated azimuths will be generated based on InterpolationFactor.
// Valid values for elevation are -45 -> +90 in 15 degree increments.
static PassOwnPtr<HRTFElevation> createForSubject(const String& subjectName, int elevation, float sampleRate);
// Given two HRTFElevations, and an interpolation factor x: 0 -> 1, returns an interpolated HRTFElevation.
static PassOwnPtr<HRTFElevation> createByInterpolatingSlices(HRTFElevation* hrtfElevation1, HRTFElevation* hrtfElevation2, float x, float sampleRate);
// Returns the list of left or right ear HRTFKernels for all the azimuths going from 0 to 360 degrees.
HRTFKernelList* kernelListL() { return m_kernelListL.get(); }
HRTFKernelList* kernelListR() { return m_kernelListR.get(); }
double elevationAngle() const { return m_elevationAngle; }
unsigned numberOfAzimuths() const { return NumberOfTotalAzimuths; }
float sampleRate() const { return m_sampleRate; }
// Returns the left and right kernels for the given azimuth index.
// The interpolated delays based on azimuthBlend: 0 -> 1 are returned in frameDelayL and frameDelayR.
void getKernelsFromAzimuth(double azimuthBlend, unsigned azimuthIndex, HRTFKernel* &kernelL, HRTFKernel* &kernelR, double& frameDelayL, double& frameDelayR);
// Spacing, in degrees, between every azimuth loaded from resource.
static const unsigned AzimuthSpacing;
// Number of azimuths loaded from resource.
static const unsigned NumberOfRawAzimuths;
// Interpolates by this factor to get the total number of azimuths from every azimuth loaded from resource.
static const unsigned InterpolationFactor;
// Total number of azimuths after interpolation.
static const unsigned NumberOfTotalAzimuths;
// Given a specific azimuth and elevation angle, returns the left and right HRTFKernel.
// Valid values for azimuth are 0 -> 345 in 15 degree increments.
// Valid values for elevation are -45 -> +90 in 15 degree increments.
// Returns true on success.
static bool calculateKernelsForAzimuthElevation(int azimuth, int elevation, float sampleRate, const String& subjectName,
RefPtr<HRTFKernel>& kernelL, RefPtr<HRTFKernel>& kernelR);
// Given a specific azimuth and elevation angle, returns the left and right HRTFKernel in kernelL and kernelR.
// This method averages the measured response using symmetry of azimuth (for example by averaging the -30.0 and +30.0 azimuth responses).
// Returns true on success.
static bool calculateSymmetricKernelsForAzimuthElevation(int azimuth, int elevation, float sampleRate, const String& subjectName,
RefPtr<HRTFKernel>& kernelL, RefPtr<HRTFKernel>& kernelR);
private:
HRTFElevation(PassOwnPtr<HRTFKernelList> kernelListL, PassOwnPtr<HRTFKernelList> kernelListR, int elevation, float sampleRate)
: m_kernelListL(kernelListL)
, m_kernelListR(kernelListR)
, m_elevationAngle(elevation)
, m_sampleRate(sampleRate)
{
}
OwnPtr<HRTFKernelList> m_kernelListL;
OwnPtr<HRTFKernelList> m_kernelListR;
double m_elevationAngle;
float m_sampleRate;
};
} // namespace WebCore
#endif // HRTFElevation_h