A stereoscopic television system (3D-TV) and compatible transmission on a MAC channel (3D-MAC)

Abstract

A new television service, in this case stereoscopic television or 3D-TV, cannot be credible unless there has been research into the analysis, transmission and restitution of 3D-TV signals. Specific studies of the quality of 3D images must give some idea of system efficiency, or even control and direct each of the above three stages. Analysis requires the use of pickup equipment capable of filming at least 2 views of the same scene. The quality of the pictures acquired in this way depends on the mechanical, optical, geometric and electronic parameters of the system. Disparity evaluation algorithms used for transmission purposes require prior knowledge of certain internal and external parameters. In this article, we propose transmission systems on a MAC type channel, which is divided into an analog and a digital section. The analog section transmits a video signal (625/50/2:1) that can be watched by any viewer with a conventional MAC receiver; this defines the notion of compatibility. The digital section is used to transmit, at a limited rate (of the order of 1 Megabit/sec), digital assistance data (‘DA’) which, in conjunction with the compatible picture, rebuilds the 3D image for a 3D receiver. Band reduction algorithms are based on frame sub-sampling and multiplexing techniques, motion and disparity compendation techniques. Their layout depends on the importance ascribed to the quality of compatible and 3D pictures, respectively, and on the output system. Display is a key element and is vital for the acceptance of 3D-TV by the general public. The present solution is the wearing of special glasses in order to synchronise the right (respectively left) eye and right (respectively left) view. However, there is no doubt that the future lies with systems that do not require special glasses, e.g. lenticular networks.