Only two can sit in the specially designed cinema booth

The Cardiff festival showcases nine films of just 15 seconds each.

They include animation, art-house, avant-garde and black comedy, and all of it lasts under three minutes.

The movies will be shown in one of the world's smallest cinemas, a specially-designed two-seater booth.

Starting on Tuesday, the two-day event also launches a competition to encourage the development of film content for mobiles phones and devices.

"Last year, the majority of Nokia Shorts entries came from London but we know there's an untapped pool of talent beyond," said Elliot Grove, director and founder of Raindance, a company which promotes and encourages independent film production worldwide.

Ushers will be at hand to lead the way in the cinema

"The World's Shortest Film Festival is designed to illustrate just what can be achieved in 15 seconds which we hope will encourage film makers from Wales to enter Nokia Shorts."

Launched last month, entries for the competition are accepted until 31 August and the winner will get the opportunity to make a longer film with a professional crew plus training courses.

To help south Wales' budding film makers come up with their film concept, a panel will be on hand during the festival to offer advice and tips on how to make an ultra-short movie.

The work of last year's nine Nokia Shorts competition finalists can each be enjoyed in just 135 seconds at the booth in the UGC, Mary Ann St, in Cardiff city centre.

"We're delighted to be hosting the world's shortest film festival," said Kate Cox, of the UGC.

"This is a truly unique concept which will entertain our customers, educate them further about independent film - and give them the motivation to have a go at film-making themselves."