1. A method of image retrieval, wherein the method includes, in a processing system: determining a query feature set for a search image, wherein the query feature set includes texture data indicative of a texture of the search image for a plurality of resolutions of the search image, wherein texture data of the search image includes a texture vector of the search image which is determined by performing the following steps: a) converting the search image to a monochromatic image; b) determining and storing in the texture vector a number of monochromatic levels of the monochromatic image; c) segmenting the monochromatic image to generate a plurality of segments; d) determining an average number of monochromatic levels for the plurality of segments of the respective segmentation; e) storing the average number of monochromatic levels for the respective segmentation in the texture vector; and f) if a segmentation condition has not been satisfied, segmenting each segment and repeating steps d) to f); determining a dissimilarity measurement between at least one query feature of the query feature set and at least one target feature of a target image set for one or more target images, wherein the dissimilarity measurement is determined at least partially based upon the dissimilarity between the texture data of the search image and one or more target images for at least some of the plurality of resolutions of the target image; and identifying one or more target images based upon the dissimilarity measurement.