Neural Nets, HSV and Histograms for face detection

Hi,
Am trying to use HSV in one of my applications to detect a face using
skin color.
Am developing a simple neural net for detecting the presence of a face
in an image.
First i resize all images into a 20x20 matrix. The i convert the image
from RGB to HSV and then split it into H,S and V values/matrices. Do i
use the H,S or V value as inputs into the net?
Then how do histograms work exactly in such a case?

Is the approach ok so far? any feedback is appreciated. Start a New Thread