Abstract: A video encoder and decoder are provided for processing a sequence of animated pictures in such a way that an interactive game, such as a puzzle for instance, may be played. Each picture of a movie sequence is divided into a predetermined number of pieces that are then randomly coded (according to the MPEG-4 standard), transmitted and/or stored, decoded and displayed. It is then possible to play with the pieces to reorder them while they are in motion (with possible associated audio), according to predefined rules and ends of scenarios. The left and right buttons of a mouse, or a similar control device, are used to displace either one piece, or a group of attached pieces respectively, in order to verify if the proposed location for a piece is free and possible (no contradiction with any other surrounding piece) and then to drop said piece on the new spot, or, on the contrary, if some contradiction is detected, send back the piece (or, respectively, the group of attached pieces) to its previous location.