Source/WebCore/platform/audio/VectorMath.h

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#pragma once

// Defines the interface for several vector math functions whose implementation will ideally be optimized.

namespace WebCore {

namespace VectorMath {

// Multiples inputVector by scalar then adds the result to outputVector (simplified vsma).
// for (n = 0; n < numberOfElementsToProcess; ++n)
//     outputVector[n] += inputVector[n] * scalar;
void multiplyByScalarThenAddToOutput(const float* inputVector, float scalar, float* outputVector, size_t numberOfElementsToProcess);

// Adds a vector inputVector2 to the product of a scalar value and a single-precision vector inputVector1 (vsma).
// for (n = 0; n < numberOfElementsToProcess; ++n)
//     outputVector[n] = inputVector1[n] * scalar + inputVector2[n];
void multiplyByScalarThenAddToVector(const float* inputVector1, float scalar, const float* inputVector2, float* outputVector, size_t numberOfElementsToProcess);

// Multiplies the sum of two vectors by a scalar value (vasm).
void addVectorsThenMultiplyByScalar(const float* inputVector1, const float* inputVector2, float scalar, float* outputVector, size_t numberOfElementsToProcess);

void multiplyByScalar(const float* inputVector, float scalar, float* outputVector, size_t numberOfElementsToProcess);
void addScalar(const float* inputVector, float scalar, float* outputVector, size_t numberOfElementsToProcess);
void add(const float* inputVector1, const float* inputVector2, float* outputVector, size_t numberOfElementsToProcess);
void substract(const float* inputVector1, const float* inputVector2, float* outputVector, size_t numberOfElementsToProcess);

// Finds the maximum magnitude of a float vector.
float maximumMagnitude(const float* inputVector, size_t numberOfElementsToProcess);

// Sums the squares of a float vector's elements (svesq).
float sumOfSquares(const float* inputVector, size_t numberOfElementsToProcess);

// For an element-by-element multiply of two float vectors.
void multiply(const float* inputVector1, const float* inputVector2, float* outputVector, size_t numberOfElementsToProcess);

// Multiplies two complex vectors (zvmul).
void multiplyComplex(const float* realVector1, const float* imagVector1, const float* realVector2, const float* imagVector2, float* realOutputVector, float* imagOutputVector, size_t numberOfElementsToProcess);

// Copies elements while clipping values to the threshold inputs.
void clamp(const float* inputVector, float mininum, float maximum, float* outputVector, size_t numberOfElementsToProcess);

void linearToDecibels(const float* inputVector, float* outputVector, size_t numberOfElementsToProcess);

// Calculates the linear interpolation between the supplied single-precision vectors
// for (n = 0; n < numberOfElementsToProcess; ++n)
//     outputVector[n] = inputVector1[n] + interpolationFactor * (inputVector2[n] - inputVector1[n]);
// NOTE: Internal implementation may modify inputVector2.
void interpolate(const float* inputVector1, float* inputVector2, float interpolationFactor, float* outputVector, size_t numberOfElementsToProcess);

} // namespace VectorMath

} // namespace WebCore