BBC director general Mark Thompson has promised that the corporation's output will provide real public service value as part of a "re-invention" process.

Speaking at the Edinburgh International Television Festival, Thompson explained that the BBC would strive to add "something distinctive and original and valuable" to programming - especially in genres such as reality TV, entertainment and light factual.

"Every couple of decades or so since its creation, the BBC has virtually re-invented itself as an institution," explained Thompson. "Each time, the BBC – apparently such a fixed and established part of British national life – has shown an astonishing ability to take a clean sheet of paper and re-imagine itself. We're approaching one of these moments again."

He pledged to shift programming priorities to certain key genres. Among them are news and current affairs, but also other areas in which the BBC is perceived to be strong such as comedy.

Thompson explained: "Although comedy is a branch of entertainment, I still think most people would accept that it too plays a critical part in reflecting our national culture and the way we live now."

The recently-appointed director general said that the changes he outlined today were part of a "searching look" within the BBC "at every aspect of what it does," timed to coincide with the ongoing Charter renewal process in which various parts of the BBC's remit are under outside scrutiny.