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Run label automation on every frame in interval


The run method computes the automated labels for a single frame by executing the automation algorithm. During automation, the labeling apps run this method in a loop to compute the automated labels for each frame in the selection being automated.

Clients of AutomationAlgorithm must implement this method.

autoLabels = run(algObj,frame) processes a single frame, frame, using the algObj automation algorithm, and returns the automated labels, autoLabels.

Input Arguments

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Automation algorithm, specified as a vision.labeler.AutomationAlgorithm object.

Frame whose labels are being computed, specified as a numeric matrix for Image signals or a pointCloud object for PointCloud signals.

Output Arguments

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Labels produced by the automation algorithm, returned as a categorical matrix, structure array, or table.

For algorithms that automate pixel labeling, implement the run method to return autoLabels as a categorical label matrix, where each category represents a pixel label. For more information, see How Labeler Apps Store Exported Pixel Labels.

For algorithms that automate nonpixel labels, implement the run method to return a structure array. Each structure in the array contains the labels of a specific name and type. The method combines labels of the same name and type into a single structure in the array.

This table describes the columns of the autoLabels table or fields of each autoLabels structure.

Field NameDescription

labelType enumeration that contains the type of the label. Valid label types are:

  • labelType.Rectangle

  • labelType.Cuboid (Ground Truth Labeler app only)

  • labelType.Line

  • labelType.Scene

NameCharacter vector containing the name of the label.

Position of labels of the specified Name and Type. The format of Position depends on the label type.

Label TypePosition Format
Rectangle — Rectangular region of interest (ROI) labels

M-by-4 numeric matrix of the form [x, y, w, h], where:

  • M is the number of labels in the frame.

  • x and y specify the upper-left corner of the rectangle.

  • w specifies the width of the rectangle, which is its length along the x-axis.

  • h specifies the height of the rectangle, which is its length along the y-axis.

ProjectedCuboid and Cuboid — Cuboid ROI labels

M-by-9 numeric matrix with rows of the form [xctr, yctr, zctr, xlen, ylen, zlen, xrot, yrot, zrot], where:

  • M is the number of labels in the frame.

  • xctr, yctr, and zctr specify the center of the cuboid.

  • xlen, ylen, and zlen specify the length of the cuboid along the x-axis, y-axis, and z-axis, respectively, before rotation has been applied.

  • xrot, yrot, and zrot specify the rotation angles for the cuboid along the x-axis, y-axis, and z-axis, respectively. These angles are clockwise-positive when looking in the forward direction of their corresponding axes.

The figure shows how these values determine the position of a cuboid.

Line — Polyline ROI labels

M-by-1 vector of cell arrays, where M is the number of labels in the frame. Each cell array contains an N-by-2 numeric matrix of the form [x1 y1; x2 y2; ... ; xN yN] for N points in the polyline.

Scene — Scene labels

Logical value of 1 if the algorithm determines that the label is present in the frame and 0 otherwise.

Attributes (optional)

Structure array that contains one structure for each attribute in the label. If the label definition does not contain attributes, then the autoLabels output does not include this field.

For each structure in the Attributes structure array, the name of that structure is the name of the corresponding attribute. The value of the structure is the value of the corresponding attribute.

To view a sample autoLabels structure array, enter this code at the MATLAB® command prompt.

autoLabels(1).Name      = 'Car';
autoLabels(1).Type      = labelType.Rectangle;
autoLabels(1).Position  = [20 20 50 50];

autoLabels(2).Name      = 'Truck';
autoLabels(2).Type      = labelType.Rectangle;
autoLabels(2).Position  = [70 70 50 50; 100 100 25 25];

Alternatively, for nonpixel labels, you can use the run method to return autoLabels as a table. The table rows are equivalent to the structures in a structure array. The table columns are equivalent to the structure fields. This table is equivalent to the sample autoLabels structure array previously specified.

        Name          Type         Position  
    ____________    _________    ____________

    'Car'           Rectangle    [1x4 double]
    'Truck'         Rectangle    [2x4 double]

Introduced in R2017a