length

Number of stored points

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Syntax

length(points)

Description

example

length(points)returns the number of stored points in the points object.

Examples

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Check Number of Stored Points

Open Live Script

Read an image.

I = imread('cameraman.tif');

Detect KAZE points from the image.

points = detectKAZEFeatures(I);

Find number of stored points.

numPoints = length(points)

numPoints = 631

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) holdonstrongestPoints = selectStrongest(validPoints,10); plot(strongestPoints,'showOrientation',true) holdoff

Figure contains an axes object. The axes object contains 3 objects of type image, line.

Input Arguments

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`points`—Points object
`KAZEPoints`object|`CornerPoints`object|`BRISKPoints`object|`SURFPoints`object|`MSERRegions`object|`ORBPoints`object|`SIFTPoints`object

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

Version History

Introduced in R2017b