My Bloody Valentine, Sufjan Stevens, Built To Spill, Mogwai, Lightning Bolt and Mercury Rev are among the artists appearing in From Ghosts, a new Kickstarter-funded documentary produced by Pitchfork.tv.
The film was shot in 2008, when All Tomorrow's Parties held its first East Coast festival in Monticello, New York.
Mogwai have been confirmed as the final headliner of this year's Green Man festival.
The Scottish rockers, who released their seventh studio album 'Hardcore Will Never Die, But You Will' in 2011, join Feist and Van Morrison in headlining the event, which takes place in Wales' Brecon Beacons from August 17-19.
Also newly added to the line-up are Dexys, Cate Le Bon, Lower Dens, Benjamin Francis Leftwich, Crybaby, Paul Thomas Saunders, Stuff, Withered Hand and King Charles.