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plot

Class: SURFPoints

Plot SURF points

Syntax

surfPoints/plot
surfPoints/plot(axesHandle,___)
surfPoints/plot(axesHandle,Name,Value)

Description

surfPoints/plot plots SURF points in the current axis.

surfPoints/plot(axesHandle,___) plots using axes with the handle axesHandle.

surfPoints/plot(axesHandle,Name,Value) additional control for the plot method specified by one or more Name,Value pair arguments.

Input Arguments

axesHandle

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

Name-Value Pair Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside single quotes (' '). You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

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Display proportional circle around feature, specified as a comma-separated pair consisting of 'ShowScale' and the logical true or false. When you set this value to true, the object draws a circle proportional to the scale of the detected feature. The circle contains 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 SURF algorithm uses this equivalent size of circular area to compute the orientation of the feature.

Display a line corresponding to feature point orientation, specified as a comma-separated pair consisting of 'ShowOrientation' and the logical 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.

Examples

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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);

Related Examples

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