Lets Learn together... Happy Reading

" Two roads diverged in a wood, and I,
I took the one less traveled by,
And that has made all the difference "-Robert Frost

Simple Image Thresholding using GUI component Slider

Thresholding is one of the steps performed on the image during image conversion. 
Also Learn: Otsu's thresholding method
It is used for separating the background from the foreground.
The user can drag the slider to adjust the Thresholding. The slider value ranges between 0 and 255.

MATLAB CODE:


function f=mainthresh()
%The window size of the image is adjusted based on the screen size.


global T1;
ssz = get(0,'ScreenSize');
figure('Visible','on','Name','IMAGE THRESHOLDING','NumberTitle','off','Position',ssz);

axes('units','pixels','Position',[ssz(3)/45 ssz(4)/4 ssz(3)-(ssz(3)/4) ssz(4)-(ssz(4)/3)]);

in=imread('coins.png');
imshow(in);
set(gca,'xtick',[],'ytick',[])

%The Slider is one of the GUI component in MATLAB. The Value of the slider is between 0 and 255.
%These values can be changed based on the image type.


slid=uicontrol('Style','Slider','Visible','on','Value',1,'Max',255,'Min',0,'Sliderstep',[1 1],'Position',[ssz(3)/35 ssz(4)/5 ssz(3)-(ssz(3)/3) 20],'Callback', @threshing_image);
ent=uicontrol('Style','pushbutton','Visible','on','String','THRESHOLD VALUE','Position',[ssz(3)-(ssz(3)/4) ssz(4)-(ssz(4)/8) 105 30]);
ed=uicontrol('Style','edit','Visible','on','String','0','Value',1,'Position',[ssz(3)-(ssz(3)/4) ssz(4)-(ssz(4)/6) 90 20]);


%When the slider is moved the corresponding position value is passed to the function 'threshing_image' .

%The original image is passed to another function 'Imthreshold'.



      function threshing_image(object,~)
        val=get(object,'value');
        in=imread('coins.png');
        T1=Imthreshold(in,val);
        imshow(T1);
        set(gca,'xtick',[],'ytick',[])
       
        set(ed,'String',val);
      end

    

%Based on the value passed, the image background is separated from the foreground.

%In this example, the background of the coins image contains pixel values less than 80.
%By adjusting the slider to value 80 the background area gets value zero and the coins appear as it is.




function Im=Imthreshold(Image,Tvalue)

%Replace the pixel value either with 0 or 255.


Image( find ( Image(:,:,1) < Tvalue ) )=255;

Im=Image;
end
f=T1;
end















Thresholded Image



Here is another example , This Image is RGB. So we have to consider the RED, GREEN and BLUE pixel values.



like button Like "IMAGE PROCESSING" page

1 comments:

Unknown said... Reply to comment

nice Greeting from Morocco.
& Thank you so much for the effort you did to help others.

Enjoyed Reading? Share Your Views

Previous Post Next Post Home
Google ping Hypersmash.com