1. A method of decoding coded digital signals representative of audiovisual data and available in the form of a continuous bitstream in view of the binary description of a scene to be rendered on a displaying device, said method comprising a processing operation based on an evolutive syntactic language and provided for extracting from said bitstream, in a first step, distinct elements called objects according to the structure of said scene, defining in a second step an individual animation of said elements of the scene, defining in a third step particular interactions between a user and said elements, and organizing in a fourth step specific relations between said scene elements and corresponding individual animations and/or user interactions according to various classes of applications, said method being further characterized in that said processing operation also includes an additional step for describing a complex scene, built from any kind of bidimensional and tridimensional objects, according to a framework integrating both bidimensional and tridimensional features and unifying the composition and representation mechanisms of the scene structure.