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isempty

Determine if points object is empty

Syntax

isempty(points)

Description

example

isempty(points) returns a true value, if the points object is empty.

Examples

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Read an image.

I = imread('cameraman.tif');

Detect KAZE points from the image.

points = detectKAZEFeatures(I);

Check for points.

if isempty(points)
    return;
end

Extract KAZE features from the detected points.

[features,validPoints] = extractFeatures(I,points);

Plot the ten strongest valid extracted points and show their orientations.

imshow(I)
hold on
strongestPoints = selectStrongest(validPoints,10);
plot(strongestPoints,'showOrientation',true)
hold off

Input Arguments

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Points object, specified as a points object. The object contains information about the feature points detected in the input image. To obtain points, use the appropriate detect function.

Introduced in R2017b