How do you convert a 2-D movie to 3-D?

# How do you convert a 2-D movie to 3-D?

Jan. 29 2010 7:13 PM

# How Do You Convert a Flat Movie Into 3-D?

## With a trained artist and a fast computer.

Following the success of James Cameron's Avatar, a 3-D science-fiction epic that became the highest-grossing movie of all time, many producers chose to convert previously filmed features to 3-D prior to release. Many have criticized the results. How do you convert a movie to 3-D after it has already been shot?

Draw a map of each shot and let a computer do the rest. 3-D movies are normally filmed using two slightly offset cameras. Both images are projected onto the viewing screen, with those cheap plastic glasses feeding one image into your left eye and the other into your right. Without the benefit of the second camera during filming, producers have to generate the two offset images based on the single flat picture that they have. The first step is to separate the shot into somewhere between two and eight layers of depth. Take, for example, an image of a man standing in front of a brick wall, with a blue sky behind the wall. The graphic artist might separate the shot into three layers: the man, the wall, and the sky. Then, he would take each layer and draw contour lines around any object that appeared there. He'd start by marking depth lines on the man using a computer, turning the image into a sort of topographical map. He'd repeat the process for any objects in the other layers. (If there were a bird in the sky, he'd draw lines there, too.)