Radio with Pictures – a New Medium

The advent of digital radio broadcasting provides the broadcaster with the opportunity to convey a variety of data types, to considerably enhance a basic audio service. Analogue FM broadcasts already benefit from a variety of features from the Radio Data System (RDS), but while RDS uses an additional carrier to convey this digital data, the emerging all-digital services such as Eureka DAB, Inmarsat IDDS and WorldSpace, have the potential to integrate all the various data types into a single channel. By the use of digital image compression standards like JPEG, it is now possible to go further: the introduction of a radio service with still pictures. Such a service is currently called 'Radio with Pictures'(RWP) and is applicable to both terrestrial and satellite delivery systems. A demonstration of the RWP concept was created, based on an edition of the BBC World satellite channel's news programme, 'The World Today'. To achieve this, a selection of representative video frames were grabbed from the full motion video, and synchronised so that their presentation coincided with the appropriate points in the original audio. The demonstration was carried out in order to investigate whether a possible RWP system could be successfully implemented from a production point of view, and also to assess the applicability of such a service. The actual demonstration programme was therefore carried over an Inmarsat IDDS satellite link, to fully demonstrate the entire process from programme production to reception. As there is currently no dedicated RWP production equipment, the process of creating an RWP programme is very time consuming. In particular, the audio video synchronisation is critical as each still frame must be timecoded to an accuracy of about one second or better relative to the audio track. This requires repeated reviewing of the RWP programme and small changes to the picture timing points. For these reasons it took an entire day to assemble a fifteen minute RWP programme to an acceptable standard. The demonstration showed the feasibility of an RWP service were it to be introduced on a Digital Audio Broadcasting (DAB) network. The difficulties of producing a fast news service using an RWP system from a television source were also stated, and ways and means for reducing the editing effort were devised. But it is clearly stated in this Report that new editing hardware and software, specifically designed for RWP operations, must be developed if success is to be assured …