How to Refine Color Identification Code?

For this project, I am trying to write code that can identify different colored skittles in a jpeg image and then report a count of (the number of) each different color skittle. So far, I have code that works decently using a binary method, but there are still issues; the count is often off somewhat. Also, before processing, the code first reduces the info in the image by pixelating it. This helps, but I have to modify how I resize the image for any given picture, which isn't ideal. The code should be able to work on any provided skittles image without being modified. I am not allowed to use loops of any kind. I have included my code. What are some ways I can refine it to work more precisely on any provided image?

    % clear;clc;close all
Published=datestr(now, 21)
figure(1)
m = imread('skittles1.jpg');
imshow(m)
[X,map]= rgb2ind(m,5);
figure(2)
imshow(X,map);
RGB = ind2rgb(X,map);
figure
imshow(RGB)
BW = im2bw(RGB);
r=m(:,:,1);
g=m(:,:,2);
b=m(:,:,3);
y = [r > 185 & r < 260 & g > 190 & g < 255 & b > -1  & b < 100];
yt=sum(y(:));
o = [r > 165 & r < 260 & g > 15 & g < 90 & b > -1 & b < 30];
ot=sum(o(:));
gr = [r > 20 & r < 95 & g > 150 & g < 230 & b > -1  & b < 70];
grt=sum(gr(:));
re = [r > 100 & r < 230 & g > 3 & g < 35 & b > 5  & b < 55];
ret=sum(re(:));
p = [r > 5 & r < 117 & g > 0 & g < 130 & b > -1  & b < 150];
pt=sum(p(:));
loc = find(re==0);
loc1 = find(re==1);
r(loc1)=0;
g(loc1)=0;
b(loc1)=0;
r(loc)=255;
g(loc)=255;
b(loc)=255;
new=cat(3,r,g,b);
figure
BW = im2bw(new);
ComplementImage=imcomplement(BW);
HolesClearedImage = imfill(ComplementImage,'holes');
cc = bwconncomp(HolesClearedImage,18);
number  = cc.NumObjects;
[labeledImage, numberOfObject] = bwlabel(HolesClearedImage);
measurements = regionprops(HolesClearedImage, 'Centroid', 'Area');
numberOfCircles = length(measurements);
imshow(HolesClearedImage)

end

[Walter Roberson]

Replaced by later http://uk.mathworks.com/matlabcentral/answers/258270-how-to-refine-color-identification-code