MATLAB: Imread and/or rgb2gray not working as expected

image analysisimage processingImage Processing ToolboxMATLAB

I am trying to read an image and convert it to grayscale. Originally, I thought the problem was with the rgb2gray function, but when I displayed the image i was trying to read, it was completely different. Here is my code (I got a part of it from another forum) as well as the picture i was trying to read and convert to grayscale.
   RGB = imread('Cir1.png');
   imshow(RGB);
   [rows columns numberOfColorChannels] = size(RGB);
   if numberOfColorChannels > 1
     Igray = rgb2gray(RGB);
   else
     Igray = RGB; % It's already gray.
   end
   imshow(Igray);
The image i am trying to read is show below.
Thanks!

Best Answer

[RGB, map, alpha] = imread('Cir1.png');
 figure ; imshow(RGB,map);
   [rows, columns, numberOfColorChannels] = size(RGB);
   if numberOfColorChannels > 1
     Igray = rgb2gray(RGB);
   else
     Igray = rgb2gray(map); 
   end
   figure ;imshow(RGB,Igray);
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