Target tracking

A method and system are disclosed for tracking a target imaged in video footage. The target may, for example, be a person moving through a crowd The method comprises the steps of: identifying a target in a first frame; generating a population of sub-templates by sampling from a template area defined around the target position; and searching for instances of the sub-templates in a second frame so as to locate the target in the second frame. Sub-templates whose instances are not consistent with the new target position are removed from the population and replaced by newly sampled sub-templates. The method can then be repeated so as to find the target in further frames. It can be implemented in a system comprising video imaging means, such as a CCTV camera, and processing means operable to carry out the method.