plot

Plot points

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Syntax

plot(points)
plot(points,ax)
plot(points,ax,Name,Value)

Description

example

plot(points) plots points in the current axis.

plot(points,ax) plots points in the specified axis.

plot(points,ax,Name,Value) sets properties using one or more name-value pairs. Enclose each property name in quotes. For example, plot('ShowOrientation',true)

Examples

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Open Live Script

Detect, extract, and plot KAZE points, including their orientation.

Read an image.

I = imread('cameraman.tif');

Detect KAZE points from the image.

points = detectKAZEFeatures(I);

Extract KAZE features from the detected points.

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

Plot the 10 strongest points and show their orientations.

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

Open Live Script

Extract SURF features from an image.

I = imread('cameraman.tif');
points = detectSURFFeatures(I);
[features, valid_points] = extractFeatures(I,points);

Visualize 10 strongest SURF features, including their scales and orientation which were determined during the descriptor extraction process.

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

Open Live Script

Read an image. 

 I = imread('cameraman.tif');

Detect corner features. 

 featurePoints = detectHarrisFeatures(I);

Plot feature image with detected features. 

 imshow(I); hold on;
 plot(featurePoints);

Input Arguments

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Points, specified as a points object. The object contains information about the feature points detected in the 2-D grayscale input image.

Handle to use for display. You can set the handle using gca.

Name-Value Pair Arguments

Example: 'ShowOrientation','true'

Display scaled circle, specified as true or false. When you set this value to true, the object draws a circle proportional to the scale of the detected feature, with the feature point located at its center. When you set this value to false, the object turns the display of the circle off.

The algorithm represents the scale of the feature with a circle of 6*Scale radius. The algorithm uses this equivalent size of circular area to compute the orientation of the feature.

Display feature point orientation, specified as true or false. When you set this value to true, the object draws a line corresponding to the point's orientation. The object draws the line from the feature point location to the edge of the circle, indicating the scale.

See Also

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Introduced in R2011b

Computer Vision Toolbox Documentation

Support