SignalProcessingExtensions.DiscreteCosineTransform Method

Computes the type-II discrete cosine transform of a vector.

Definition

Namespace: Numerics.NET.SignalProcessing
Assembly: Numerics.NET (in Numerics.NET.dll) Version: 10.9.0

public static Vector<double> DiscreteCosineTransform(
	this Vector<double> x,
	bool orthonormal = true
)

Visual Basic

<ExtensionAttribute>
Public Shared Function DiscreteCosineTransform ( 
	x As Vector(Of Double),
	Optional orthonormal As Boolean = true
) As Vector(Of Double)

C++/CLI

public:
[ExtensionAttribute]
static Vector<double>^ DiscreteCosineTransform(
	Vector<double>^ x, 
	bool orthonormal = true
)

[<ExtensionAttribute>]
static member DiscreteCosineTransform : 
        x : Vector<float> * 
        ?orthonormal : bool 
(* Defaults:
        let _orthonormal = defaultArg orthonormal true
*)
-> Vector<float>

Parameters

x Vector<Double>: The vector to transform.
orthonormal Boolean (Optional): Optional. Specifies whether the transform should be orthogonal/unitary. The default is true.

Return Value

Vector<Double>
The discrete cosine transform (DCT) of x.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type Vector<Double>. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

Remarks

When orthonormal is false, coefficient k is twice the sum of x[j] cos(pi (j + 1/2) k / N). The orthonormal form uses scale sqrt(1/N) for k=0 and sqrt(2/N) for the remaining cosine sums.