1. An image processing method by a client device, comprising the steps of: partitioning an image under test to form a plurality of image segments, each segment representing a set of pixels having similar image properties; deriving feature data from a subset comprising one or more of the image segments; transmitting at least the feature data to a server device; receiving, from the server device, data indicative of a purchasable article or service associated with the reference feature data detected to be most similar to the feature data of one or more of the image segments; and displaying purchase details of the article or service.