How to use improfile taking image from UIaxes in App designer

Hello!

I'm developing a windows application to demonstrate image profile as a program reaction to button click. Unfortunately I do not understand how I can use improfile function taking the image as a parameter from a UIAxes component of my application.

As I understand it must be really simple. I tried to pass the UIAxes as parameter, but it failes.

I will appreciate any guidance from Matlab community. Thank you in advance!

[Walter Roberson]

Have you used image() or imagesc() or imshow() to display an "image" to the UIAxis ? Or is it something else completely, such as a pcolor() or a patch or a histogram?

Answer 1

[Praveen Reddy]

Hi Igor,

I understand that you want to pass image on the app designer UI axes as input to “improfile” function. Here is one way to do it in the call back function.

• Read the image from app UI Axes using “getframe” function
• Convert the image to grayscale
• Define starting and ending coordinates for the profile.
• Pass the grayscale image along with starting and ending coordinates as shown below.

function profileButtonPushed(app, event) 
    frame=getframe(app.UIAxes); %axes handle from which image has to be obtained 
    rgbImage = frame.cdata; 
    grayImage=rgb2gray(rgbImage); 
    x1 = 100; % starting x-coordinate 
    y1 = 100; % starting y-coordinate 
    x2 = 200; % ending x-coordinate 
    y2 = 200; % ending y-coordinate   
    profile = improfile(grayImage, [x1, x2], [y1, y2]); 
    plot(app.UIAxes2,profile); 
end 

Attaching an .mlapp file for reference where “improfile” function takes input from UI Axes.

Please refer to the following MATLAB documentations to know more about “improfile”, “getframe” functions.

• https://in.mathworks.com/help/images/ref/improfile.html
• https://in.mathworks.com/help/matlab/ref/getframe.html

[Igor Grishin]

Thank you very much for the idea! Definitely worth to try.