NXVision (2007-11)

Title: Improvements to embedded secure placeshifting technologies
Research Engineer: Chris Windmill
Sponsor: NXVision, Dunfermline
Academic Supervision: Dr John Hannah, University of Edinburgh
Industrial Supervision: Dr Glenn Craib, CTO

Founded in September 2006, NXVision is developing a unique solution to deliver a truly mobile television experience, allowing end users to access a personal set-top box, and watch content anywhere in the world. The goal is to add capability and device support to placeshifting technology. The company’s technology requires a number of challenging developments in embedded software design, and topics for research may include:

• Audio / video codecs for embedded applications
  Within embedded placeshifting there is a requirement for adding extra capability to the STB in the form of video and audio transcoders. These are needed to take the incoming audio / video from the broadcast format (typically MPEG2 for SD broadcasts) and transcode / transrate to a more efficient format, as well as a lower bit rate / frames size. The output formats required are H.264 for video and AAC for audio. There is a need to reduce the code footprint, dynamic memory requirements and processor overhead, which will allow the technology to be used with a wider range of boxes.

Placeshifting requires a client device, such as a PC or mobile phone. Within some of these devices, H.264 / AAC decoders already exist (such as those using a Symbian operating system). Other devices require that this capability be added, which has a similar requirement to that for the STB (low memory footprint, processor overhead etc). The research would involve studying available codecs, optimising portability between devices, and evaluating the most cost effective solution.

• Quality of service algorithms
  Placeshifting relies on sending AV to a remote location over the internet. The placeshifting system has to measure the quality of service dynamically, and adjust the audio and video encode rates depending on the actual bandwidth available. The research would study various quality of service measurements, as well as profiling network responses, in order to propose a better, faster, lower overhead method of ensuring the user gets a good quality of service.
  
  
• Mobile digital rights management
  This project would centre around a study into the different mobile DRMs which are suitable for use with the Inxstor secure placeshifting solution. These DRMs need to be evaluated for suitability for embedding into the STB and client devices. The project needs to recommend a strategy for adopting mobile DRM solutions, as well as suggesting alternative approaches for ensuring the AV transfer is secure.