Skin color segmentation process

Detection of skin color in color images is a very popular and useful technique for face detection. Many techniques exists have reported for locating skin color regions in the input image. While the input color image is typically in the RGB format, these techniques usually use color components in the color space, such as the HSV or YIQ formats. That is because RGB components are subject to the lighting conditions thus the face detection may fail if the lighting condition changes. Among many color spaces, this project used YCbCr components since it is one of existing Matlab functions thus would save the computation time. In the YCbCr color space, the luminance information is contained in Y component; and, the chrominance information is in Cb and Cr. Therefore, the luminance information can be easily de-embedded. The RGB components were converted to the YCbCr components using the following formula given by



Threshold value is chosen by the following equation given by






Our proposed skin color segmentation is described below:
Two rules to segment skin color pixels from inputted RGB image:

R1: R>G>B
R2: R-G>=45

If both R1 and R2 are true then the pixel is considered as skin color pixel. We put a black pixel for the skin color pixels and put white pixel for non-skin color pixels.

Comparison with two system: