Challenges and Opportunities for 4G Wireless Video

As depicted in the illustration below, the world has become a content producer. People create and upload their own pieces of art onto the network while enjoying other people’s masterpieces. It may be expected that in 4G the communication networks will continue to expand so as to include all kinds of channels with various throughputs, quality of services and protocols, and heterogeneous terminals with a wide range of capabilities, accessibilities and user preference. 

Thus the gap between the richness of multimedia content and the variation of techniques for content access and delivery will increase dramatically. Against such a background of expectations of universal multimedia access (UMA) will become a challenge for the 4G wireless network. The major concept of UMA is universal or seamless access to multimedia content by automatic selection or adaptation of content following user interaction.

Content-based interactivity is highly connected to UMA but imposes higher expectations and requirements on content understanding supports. In the 4G high-speed communication systems, the mobile TV user may customize the content by manipulating the text, image, audio, video and graphics, and may even access information that is not available in the current system. Consequently, the 4G wireless system may face the challenge that watching TV or movie has been changed from a passive activity to a new user experience with much higher interactivity. Mobile TV has been a network killer application for a long time, the supported resolution of TV clips by mobile devices has increased dramatically

It is expected that high-definition (HD) TV programmes will soon be delivered to and played in mobile devices in 4G networks, although there are still many challenges to be faced.

On the other hand, video on TV has not been flat for much longer; following advancements to 3D video or 3D TV services over 4G wireless networks with various representation formats.

As shown in the Graph here, the expected road map for reality video over wireless was predicted by the Japanese wireless industry, and it is interesting that the expected deployment of stereo/multi-view/hologram is around the same time period as that of 4G. Currently, stereoscopic and multi-view 3D videos are more developed than other 3D video representation formats, as their coding approaches are standardized in MPEG ‘video-plus-depth’ and JVT MVC standards, respectively. It is also claimed that coded 3D video only takes a 1.2 bit rate as compared to monoscopic video (i.e., the traditional 2D video). Clearly, higher reality requirements will bring in a larger volume of data to be delivered over the network, and more service and usage scenarios to challenge the 4G wireless infrastructures and protocols.

Recently, P2P (peer-to-peer) live video streaming has become very popular as it needs much less deployment cost and is able to take advantage of the distributed storage and computing resources in the network. The basic idea of P2P is to treat every node in the network as a peer and the peer can help to pass the video packets to others. However, in the 4G system, the large scale P2P wireless video streaming capability of supporting many viewers would still be very challenging, considering the difficulties of effective incentive mechanisms for peers willing to collaborate, peers’ media relay capability, peers’ system topology discovery capability, QoS control, etc.

Finally, as so many fancy applications and services are expected to be deployed in 4G networks, the cross-layer design mechanism for content delivery with satisfactory quality of user experience becomes critical.