> REAL TIME TRANSCODING AND ADAPTATION

Real time transcoding and adaptation

The content produced by SkyMedia end-to-end architecture must undergo a series of transformations before delivery phase and for this reason an advanced methodology for 3D/HD transcoding and adaptation is deployed. The procedure of transcoding (i.e. the transformation of the format or parameters of a multimedia stream) is an absolute necessity which must be executed in real time. Since transcoding is applied in many different forms depending the devices/networks/services requirements in the case of SkyMedia it has to justify or deal with the following minimum set of goals: format conversion, bit-rate reduction, spatial/temporal resolution reduction, content enrichment. Additionally integrity and quality of both HD and 3D content has to be preserved all along the chain meaning that both error resilience and concealment should be guaranteed in order to be compliant with multimedia content transmission over error prone wireless networks. Smart image and video transcoding has also to be developed and tested to ensure that media quality remains constant or at least acceptable over time. Heterogeneous mobile devices will have to be handled through efficient scalable coding and transcoding techniques.

Today one can find an abundance of proposed transcoding solutions for audiovisual content delivery over wireless video distribution networks, for IP-video and multimedia over web, and other. The majority of them are concerned with the 2D transcoding for the reduction of the bit-rate and spatial/temporal resolution while maintaining acceptable quality. Methods differ in the transformation methodology delivered and the applied strategies for quality refinement (e.g. refinement of motion vectors for MPEG formats). Generally it seems interesting to work in the transformation domain (especially compression) researching methodologies to reduce complexity and latency however maintenance of quality in all cases remains an open challenge. SkyMedia applies advanced transcoding in 3D formats along with some innovative techniques for real time adaptation.

SkyMedia targets to develop a platform independent video transcoding technology geared towards the processing of 3D and HD content. Such a transcoding platform will have to encompass all the coding formats necessary in the underlying end-to-end architecture, performing with low latency and without infringement of the end-to-end real time requirement while guaranteeing high final quality for a plethora of different devices. Optimization of image and video coding and transcoding is required in order to allow improved coding efficiency and enhanced data rate-distortion allocation as well as content format and coding adaption for seamless distribution on an end-to-end architecture.