im loading a pic onion.png and using function kmeans(x,k) i assigned k=5. now problem is that i cant find what 'x' is and how to use it? i want to cluster whole image based on its 5 colors. never used matlab so dont know how to use the functions

Code that i wrote till now

a=imread('onion.png');
imshow(a);
ab=double(a);
cluster=kmeans(ab, 5);
finalImage=reshape(cluster ,5);
figure, imagesc(finalImage)

[Laila Hayat]

some one please give me some hint

Answer 1

[Image Analyst]

Do you have the stats and image processing toolboxes? If so, just follow this example: http://www.mathworks.com/products/demos/image/color_seg_k/ipexhistology.html Or else get the colors one at a time using any of the methods in my File Exchange: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862