Channel 4 boss Mark Thompson is to give his views on the state of the television industry when he delivers the annual McTaggart lecture in Edinburgh on Friday.

The keynote speech at the Edinburgh Television Festival has been given by senior industry figures including BBC director general Greg Dyke and ITV boss David Liddiment in the past.

The event has occasionally been used as a forum to demand changes to the way the BBC operates.

Chris Evans is also among the festival speakers

And it has been reported that Mr Thompson, the former BBC director of television, may explain why he has changed his stance on the corporation's youth television channel after he left.

He championed the proposed youth digital channel, BBC Three, while with the corporation - but his new channel has said the plan will damage commercial stations.

The speech is the main event at the TV industry's annual talking shop and often sparks wide debate.

Industry figures will also be interested to hear Mr Thompson's vision for the future of Channel 4.

The channel has recently gone through troubled times, registering its first loss in a decade and scaling back film-making arm FilmFour.

On-screen talent

The threat of more job losses still hangs over the channel as it goes through a period of transition.

The McTaggart speech, which traditionally opens the festival, was used by Dyke to announce he was controversially scrapping the Nine O'Clock News and moving the bulletin to 2200.

The festival sees hundreds of TV executives and screen stars gathering for a series of discussions and debates about trends in the industry.

Already on Friday, Ricky Gervais and Stephen Merchant, creators and stars of The Office, revealed their much-awaited second series is set to ruffle a lot more feathers than the first, with the introduction of new characters upon which manager David Brent practices his vulgarity.

Merchant and and Gervais showed a festival audience a clip from episode five of the new BBC Two comedy series, scheduled for September, in which all the staff of the Slough firm are taking part in Red Nose Day. One is dressed as Wonder Woman, another as Ali G.

Gervais told the festival audience that the second series would be "the same but different" because it was the chance to develop the characters and push things a bit further.

Among the other sessions this year will be an appearance by broadcaster Chris Evans - the presenter who turns TV producer for forthcoming Channel 4 and Channel 5 shows - who will be quizzed on his views about the TV industry.