function drawpixels(img,s)
data=double(imread(img));
a=size(data);
global image_data;
for k=1:1:3
    t=(k-1)*8;
    for i=1:1:a(1)
        for j=1:1:a(2)
            m=floor((data(i,j,k))/32)+t;
            if (m==s)
                image_data(i,j,1)=1;
            end
        end
    end
end