YouTube film "Life in a Day" coming to theaters

(CBS) - One year ago YouTube viewers were asked to upload a video reflecting a day in their lives. According to the filmmakers, people from all over the world uploaded 80,000 videos with 4500 hours of footage.

The result is the 90-minute documentary "Life in a Day." It's been described as "a historic cinematic experiment to create a documentary film about a single day on earth."

Presented by YouTube and National Geographic, the film has a mighty duo of Ridley Scott producing and Kevin Macdonald directing.

The trailer reveals stirring snippets of people talking about love and fear. In a National Geographic discussion with the filmmakers, Macdonald talked about the challenge of creating a narrative for the documentary. He asked contributors to tell their stories, talk about fears and show what was in their pockets. "It offered us wonderful 'time capsule' material," said editor Joe Walker. 

Footage that didn't make the cut will be posted on the project's YouTube channel.

Early reviews are good, though mixed. The Guardian described it as "enjoyable, as upbeat and happy as a pop video." Variety says, "[Audiences] willing to lose themselves in a kind of Internet-style armchair adventure will doubtless be swept up, though more critical eyes will note that the Western world is considerably on greater view in this assemblage than contributions from Latin America, Asia and Africa."

Ridley Scott is best known for directing films like "Alien," "Blade Runner" and "Gladiator." Kevin MacDonald is best known for directing "The Last King of Scotland" and has won an Academy Award for the documentary "One Day in September."

The film premieres on Friday, July 29 in select theaters.