1. A method in a computing system for generating a detector to detect a dominant color of an image, the method comprising: providing a collection of training images; for each training image, identifying candidate dominant colors of the training image; extracting features of the candidate dominant colors of the training image; and inputting indications of dominance of the candidate dominant colors to the training image; and training a detector to detect a dominant color of the image using the extracted features and indications of dominance of the candidate dominant colors.