Color Detection on Images by Using MATLAB

Color Detection in Image by using MATLAB

• So as to do the Color Recognition in Images utilizing MATLAB, first of all, we require a Picture.

• Therefore, I Designed a picture in paint that has diverse shapes in various hues as appeared in beneath picture:
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• There are distinctive shapes and colors in the picture, we will distinguish these shapes by their colors.

• Copy/Paste the give code into your m File.

   data = imread('TEP.jpg');
   diff_im = imsubtract(data(:,:,2), rgb2gray(data));
   %Use a median filter to filter out noise
   diff_im = medfilt2(diff_im, [3 3]);
   diff_im = im2bw(diff_im,0.18);
   
   diff_im = bwareaopen(diff_im,300);
   
   bw = bwlabel(diff_im, ;
   
   stats = regionprops(bw, 'BoundingBox', 'Centroid');
   
   % Display the image
   imshow(data)
   
   hold on

   for object = 1:length(stats)
       bb = stats(object).BoundingBox;
       bc = stats(object).Centroid;
       rectangle('Position',bb,'EdgeColor','r','LineWidth',2)
       plot(bc(1),bc(2), '-m+')
       a=text(bc(1)+15,bc(2), strcat('X: ', num2str(round(bc(1))), ' Y: ', num2str(round(bc(2)))));
       set(a, 'FontName', 'Arial', 'FontWeight', 'bold', 'FontSize', 12, 'Color', 'black');
   end
   
   hold off

• After implementing the code, Execute the m file, if there is no error, you will get the output.
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  You can find in the above figure, we have just recognized the shapes with green shading.




• The + sign demonstrates the focal point of each distinguished shape.




• X and Y are the x,y directions of the mid point of every shape that are appeared in dark for every recognized shape.




• Presently, We have distinguished red Shapes in the Pic, so keeping in mind the end goal to do as such what I have to do is to just change the third esteem in imsubtract capacity from 2 to 1.

• If you run this code in MATLAB, then your output will be like that:




• Now, it recognized the red shapes/Objectives in MATLAB.

• Its x,y coordinates are in Dark Color.
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  In the end we will identify the blue shading, to do so, you simply have to change the third parameter to 3 and it will distinguish the blue shading like this: