Digital Television Backward Compatibility Based on Mixed Simulcast using Independent Scalable Video Coding

A significant problem in digital television broadcasting is the introduction of new coding techniques when new formats arrive. If the new codec is not fully compatible with the previous one, then backward compatibility is lost. Typically, when incompatible video coding technologies are used, the solution is to begin a simulcast model. This paper discusses one technique to circumvent this problem. The technique is based on the idea of a mixed simulcast. It is based on the concept of spatial scalability without sharing information between different encoding algorithms. This paper explains the application of this technique to the combination of an MPEG-2 video codec with SD signals and an H.264/AVC video codec with HD signals. While the focus here is on the introduction of HD in a DVB-T network without losing compatibility with legacy SD devices, the method described can also address the transition from HD to UHD.