Thursday 30 July 1998
FACTS Specialist Group-DTTB has moved forward to choosing further technical elements of the Australian digital television system.
Following the recommendation of the DTTB Selection Panel that Australia should adopt the DVB-T modulation system, Specialist Group-DTTB has unanimously decided to recommend choices for a preferred HDTV production format, for digital encoding system for program sound and for the basis for developing the service information data stream for the digital television system.
Each of these elements has been examined by expert groups who have examined the available options with the aim of establishing which systems will provide the best choice for the Australian service.
The preferred video format for HDTV production purposes is 1920/1080/50Hz interlaced with a total line count of 1125 lines. Adoption of this resolution does not limit a broadcaster to this format solely, but rather implies that this is the preferred specification for HDTV equipment purchases and for interchange of product.
For audio, AC3 has been recommended as the preferred method of encoding audio prior to modulation. While this does not preclude the use of other audio encoding where necessary, the decision was taken on the grounds of technical performance, the large population of audio products that exist within the community, and the existing widespread licensing arrangements that are in place between Dolby and many manufacturers.
The Chairman of the Specialist Group, Bruce Robertson said that the choices made for the production format and audio encoding will bring Australia into line with the US HDTV display and audio formats, thereby gaining access to price advantages associated with an extremely large and evolving market. This advantage applies to broadcaster equipment and consumer goods, both of which will only require a change in the scanning rate for 60Hz (US) to 50 (Australia). Several large manufacturers have advised that this is a simple alteration which will have minimal impact on cost.
A further decision taken this week was for the Service Information data standard for Australian terrestrial TV to be based on the DVB-SI standard. That standard will need to be supplemented to define the total Australian requirements, for example use of AC3 for audio at 50Hz and the Australian PAL TV system. The DVB-SI basic system was found to meet more of the essential Australian requirements than the US alternative, PSIP standard.
Mr Robertson indicated that with the key recommendations for high definition standards and the transmission format now taken, the way is cleared for the industry to prepare the detailed specifications by the end of this year. He said this timing was essential for the broadcasting industry and the receiver production industry to be able to meet the Government’s January 2001 timetable.
For further information:
Tel: (02) 9960-2622
Tel: (02) 9906 9999