How can I extract one-dimentional color histograms features?

Hi All,

I have an image and I need to extract local features,so I divided it to 32 * 32 patches and size of each patch =16 *16 pixels and extract that three color histograms features locally from each patch,I read a paper that used one-dimentional color histograms as features but I am confused what it means by one-dimentional color histograms?and which matlab function calculate it

by using

 [counts, x] = imhist (patch) 
, I think that the counts are local features(is it correct)?

or by using

hist(patch) ?