It is the first time ITV, Channel 4 and Five have demonstrated their interest in HD, while the BBC is extending its involvement in the emerging technology.
The trial is due to run in the summer and will feature programming from ITV including its World Cup matches, nature documentaries and other programming.
There were no details available on the programming being contributed by the other three broadcasters. The BBC is using World Cup and Wimbledon coverage, as well as recent nature series 'Planet Earth', in its own trials due to start on May 15.
Simon Fell, controller of emerging technologies at ITV, said: "ITV is already commissioning and recording a wide range of HD programming.
"This trial will allow us to evaluate the technology and give us valuable insight into viewer attitudes to HD, helping to show the possibilities for HD broadcasts over DTT post-switchover."
Ofcom has allowed the trial to use local digital terrestrial frequencies.
Sky has already confirmed its HDTV service is to launch in May. It will offer programming including its own football and cricket coverage as well as the BBC's World Cup and Wimbledon coverage, movies and arts programming, and Sky One shows such as '24'.
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