The late Robert Altman, a Croisette regular since winning the Palme d’Or for “MASH” in 1970, returns to Cannes as the subject of “Altman,” an authorized feature bio-doc set to start lensing this fall.

Helmed by Ron Mann (“Comic Book Confidential,” “Grass,” “Go Further”), pic is being produced by Mann’s Toronto-based Sphinx as an Epix Original Documentary in association with Astral’s the Movie Network (TMN).

Epix — a joint TV, VOD, online and consumer electronics venture between Viacom and its Paramount unit, MGM and Lionsgate — has U.S. cable and broadcast rights;TMN has Canuck TV rights.

Submarine Entertainment’s David Koh and Josh and Dan Braun, and co-financer Stanley Buchthal of the Dakota Group, negotiated the deals and are handling worldwide theatrical sales. They are presenting the film to buyers at the Cannes Market.

Mann’s own distribution shingle Films We Like has taken Canuck theatrical.

A longtime Altman fan, Mann began the project last fall, just weeks before attending the Torino film festival, which was holding a massive Altman retrospective. There, Mann met with the filmmaker’s widow, Kathryn Reed Altman, and producer Matthew Seig, both of whom later agreed to support and consult on the doc.

“Altman defined cinema for me — he had an extrordinarily rollicking career, ” said Mann

Seven Altman films played in the Cannes competition; besides the 1970 Palme win, he nabbed best director in 1992 for “The Player.”

“It’s here at Cannes where his career really took off,” Mann said. “He was a regular, so of course we are looking at the stock footage from the festival’s archives.”

The completion target for “Altman” is mid 2013, and there are firm plans under way for a touring exhibition, illustrated companion book and soundtrack to accompany its theatrical release.