Image caption Dan Bettridge performs at a Swn showcase at Clwb Ifor Bach

Cardiff's Swn music festival will return in a changed format - spanning a month and visiting venues across Wales.

The festival usually takes place over a weekend in the capital, championing up-and-coming acts.

But co-founder John Rostron said the 11th edition would be "very different" when he announced part of the line-up on Tuesday.

It will start in Swansea on 22 September and will incorporate the Welsh Music Prize.

The Skints' performance at Sin City will kick off the festival and follows calls to move events around the country.

But Mr Rostron said that while a few gigs will be held around Wales, Cardiff will remain "at the heart of it".

Speaking to BBC Radio Wales' Good Morning Wales programme, Mr Rostron announced gigs at venues such as Clwb Ifor Bach, The Tramshed and The Globe.

Image caption Award-winning musician Gwenno was celebrated in a mural on the side of Clwb Ifor Bach

In the past year, Dempsey's and The Full Moon - prominent Swn Festival locations - have closed.

"Cardiff changes fast and every year. What works one year doesn't the next," Mr Rostron said.

"We have lost a lot of small venues in the past year. Instead of buying a wristband and running round, it will look very different [this year] because the city looks very different."

The Welsh Music Prize is usually awarded in November but Mr Rostron said it has a "natural home" at the festival.

He added that packing the event into four days made it difficult to expand the festival's programme and that the new month-long format has given it far more flexibility.