I have to name different colors in a single image(Not the dominant color),How to take feature vector? What is procedure for taking local and and Global features? I have to map HSV values into color name

I have an image with different colors. I have to recognize the colors present in the image. I am mapping HSV values to a color name. I have to get a feature vector that contains Hue saturation and Value. I have to assign a color name for a particular patch. How to extract color features for this problem?