Abstract: An editing system is proposed for automatically, or semi-automatically, editing input data to generate output production. The input material is annotated by, or analyzed to derive, a set of media descriptors which describe the input material and which are derived from the input material. The style of editing is controlled using style data which is optionally derived from a user. The input material may include any or more of motion video, still images, music, speech, sound effects, animated graphics and text. The style data and the descriptors are used to generate a set of operations which, when carried out on the input data, generate an edited output production.