Hybrid compression of video with graphics in DVT communication systems

M. van der Schaar, P.H.N. de With
2000 Digest of Technical Papers. International Conference on Consumer Electronics. Nineteenth in the Series (Cat. No.00CH37102)  
Advanced broadcast manipulation of TV sequences and enhanced user interfaces for TV systems have resulted i n an increased amount of preand post-editing of video sequences, w h e r e graphical information is inserted. However, i n the current broadcasting chain, there are no provisions for enabling an efficient transmission/storage of these mixed video and graphics signals and, at this emerging stage of DTV systems, introducing new standards is not desired. Nevertheless, in the professional
more » ... he professional video communication chain b e t w e e n content provider and broadcaster and locally, i n the DTV receiver, proprietary video-graphics compression schemes can be used to enable m o r e efficient transmission/storage of mixed video and graphics signals. For example, in the DTV receiver case, this will lead to a significant memory-cost reduction. To preserve a high overall image quality, the video and graphics data require independent coding systems, matched w i t h their specific visual and statistical properties. In t h i s paper, w e introduce various efficient algorithms that s u p p o r t both the lossless (contour, r u n l e n g t h and arithmetic coding) and the lossy (block predictive coding) compression of graphics data. If the graphics d a t a are apriori mixed w i t h video and the graphics position is unknown at compression time, an a c c u r a t e detection mechanism is applied to distinguish the t w o signals, such that independent coding algorithms can be employed for each data-type. In the DTV memory-reduction scenario, an overall bit-rate control completes the system, ensuring a fixed compression factor of 2-3 per f r a m e without sacrificing the quality of the graphics. Keywords-TV c o m m u n i c a t i o n systems, lossless i m a g e c o m p r e s s i o n , graphics, c o n t o u r c o d i n g , a r i t h m e t i c c o d i n g , r u n l e n g t h c o d i n g , e m b e d d e d c o m p r e s s i o n architecture. . Per August 2000, he is with CMG Netherlands and the University of Technology Eindhoven. the gradual transition to digital equipment is also taking place locally at the broadcaster and the DTV-receiver side. Therefore, the efficient storage of video and graphics signals becomes important also for these systems. It is relevant to notice that for these architecturesprofessional communication chain and local storage at content provider, broadcaster and receiverno standardized compression algorithms are required, thereby allowing for differentiation between the various manufacturers. For example, recently, several algorithms have been proposed for reducing the video storage of the DTV-receivers [15] [16] [14] [13]. How-
doi:10.1109/icce.2000.854648 fatcat:imws6fhtyvc2bdzdy7zp2d5uiy