1. A computer-implemented method of image retrieval from a target image collection, the steps performed by a computer system and comprising: segmenting a query image into two or more bands; obtaining weighted colour histogram vectors for the two or more bands in the query image; obtaining weighted colour histogram vectors for two or more bands in a target image; and, determining a distance measurement between the query image and the target image using the weighted colour histogram vectors from corresponding bands in the query image and the target image.