dsp Forum - Future of Video Coding and Transmission
T his discussion focuses on aspects of video coding and transmission that are relevant for next-generation services. The moderators and the forum members bring their expert insights into issues such as video coding performance, architectures (block based, scalable, distributed), robustness, multi-view video coding, and visual quality. The invited forum members are: associate editor of IEEE Signal Processing Magazine). Our readers may agree or disagree with the ideas discussed here. In either case, we invite you to share your comments with us by e-mailing avetro@merl.com and barni@dii.unisi.it. E. Delp: Is video coding dead? Some feel that, with the higher coding efficiency of the H.264/MPEG-4 Advanced Video Coding (AVC) standard (2x as compared to MPEG-2), perhaps there is not much more to do. I must admit that I have heard this " compression is dead " argument at least four times since I started working in image and video coding in 1976. J-R. Ohm: There could be different reasons to potentially conclude that no further research in video coding is necessary. From an academic perspective, the end of the story will be reached when we have reached a known bound of compression. For example, this has been the case in channel coding for the additive Gaussian white noise channel (AWGN): after the existence of the Shannon bound was proven, it took about 50 years to actually reach the bound with a practical (i.e., acceptable complexity) scheme. For video signals, we just know that there must be such a bound as well. In other words, for some given distortion we will need to spend some rate typically above zero; but video signals are so complex and so more difficult to be modeled compared to the AGWN channel that we do not know where such a bound actually could be. I personally do not believe we are there yet. Even if we were there, it might be worthwhile to look into the problem of achieving the same bound with less complexity. Currently, the main goal still seems to be walking towards that bound (improving compression) without increasing complexity too much. This goal could still keep the video coding research alive for a couple of years or decades. The same does not apply to industry, where the increasing bandwidth of networks and capacity of storage devices may decrease the need for better compression. G. Sullivan: Another " compression is dead " argument that I've heard …