how to use slider for image processing?

Hello guys, I want to ask about slider in GUI. How do I use the slider for increment level value to thresholding grayscale image and then show it in the axes box? I hope you guys understand,please help me.

Answer 1

[Image Analyst]

First set up the min and max properties, like 0 and 255, either in GUIDE or in your code. Then, when you need to use its value, get the slider value from any callback like this:

sliderValue = handles.slider1.Value;

Then use it to binarize an image like

binaryImage = grayImage > sliderValue;
imshow(binaryImage);

or however you want to use it.

[Varian Adisuryo]

Thank you so much for your kind help. I will try to make it. Thank you so much

[Varian Adisuryo]

Hi Mr. Image Analyst, I've done it like you said and combine from your answer from another question in this forum but when I run it, the the result in the axes is just blank white whenever I move the slider. I'm a beginner at this so would you please to correct my script?

a=getappdata(0,'a');

a_gray=rgb2gray(a);

thresholdValue = uint8(get(handles.slider1, 'Value'));

sliderValue = get(handles.slider1, 'Value');

a_bw=im2bw(a_gray,thresholdValue);

axes(handles.axes2);

imshow(a_bw)

I'm very sorry if my script is confusing for you. please help

[Adam]

Did you set the slider max to 255?

[Varian Adisuryo]

wow thank you so much Mr. Adam, thank you so much. I changed the slider max to 255 and it works!! Thank you so much :)

[Bram Mast]

Hi Varian

How did you finally implement this ?

[Image Analyst]

I imagine he used my code. But you might switch now to App Designer instead of GUIDE as that's their new way forward.