The ITU Radiocommunication Assembly considering a)that several broadcasters around the world desire to deliver programmes of enhanced perceived picture quality to their audiences without the need to introduce changes in the specifications of the delivered video signal;b)that in particular, the current implementation of HDTV broadcasting in several countries,and the availability of prerecorded programmes of HDTV picture quality, in the form of HD capable DVDs for consumer use, contribute to the broadcasters’ desire to increase the perceived picture quality of the SDTV programmes they deliver to their audiences, while retaining compatibility with existing SDTV receivers.