step

System object: dsp.Variance
Package: dsp

Variance of input

Syntax

Y = step(H,X)
Y = step(H,X,R)
VAR2D = step(H,X,ROI)
VAR2D = step(H,X,LABEL,LABELNUMBERS)
[VAR2D,FLAG] = step(H,X,ROI)
[VAR2D,FLAG] = step(H,X,LABEL,LABELNUMBERS)

Description

Y = step(H,X) computes the variance, Y, of input X over successive calls to the step method, when the RunningVariance property is true.

Y = step(H,X,R) resets its state based on the value of reset signal R , the ResetInputPort property and the ResetCondition property. This option applies when the RunningVariance property is true and the ResetInputPort property is set to true.

VAR2D = step(H,X,ROI) computes the variance of input image, X, within the given region of interest, ROI , when the ROIProcessing property is true and the ROIForm property is Lines, Rectangles or Binary mask. Full ROI processing support requires a Computer Vision System Toolbox™ license. With only the DSP System Toolbox™ license, the ROIForm property only supports Rectangles.

VAR2D = step(H,X,LABEL,LABELNUMBERS) computes the variance of input image, X, for region labels contained in vector LABELNUMBERS , with matrix LABEL marking pixels of different regions. This option is available when the ROIProcessing property is true and the ROIForm property is Label matrix.

[VAR2D,FLAG] = step(H,X,ROI) returns FLAG which indicates whether the given region of interest is within the image bounds when both the ROIProcessing and ValidityOutputPort properties are true and the ROIForm property is set to Lines, Rectangles or Binary mask.

[VAR2D,FLAG] = step(H,X,LABEL,LABELNUMBERS) returns FLAG which indicates whether the input label numbers are valid when both the ROIProcessing and ValidityOutputPort properties are true and the ROIForm property is set to Label matrix.

    Note:   H specifies the System object™ on which to run this step method.

    The object performs an initialization the first time the step method is executed. This initialization locks nontunable properties and input specifications, such as dimensions, complexity, and data type of the input data. If you change a nontunable property or an input specification, the System object issues an error. To change nontunable properties or inputs, you must first call the release method to unlock the object.

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