We wrestled with a couple of different ways to do this. We would come close, but even the slightest defect — when you actually viewed it in 3-D, it jumped right out at your eyes. – BYU computer science professor Bryan Morse

PROVO — A team of researchers from BYU and Adobe has developed a technique that could one day allow home photographers to edit their 3-D photos and display them as naturally as a normal 2-D digital photograph.

In theory, editing 3-D photos should be no more difficult than editing 2-D images, BYU computer science professor Bryan Morse said, because 3-D photos are essentially composed of two 2-D images, taken a few inches apart. Human eyes use a similar trick to see depth. But human eyes are so effective at inferring depth when presented with two images that even the slightest defect becomes immediately apparent. That, Morse said, is what makes 3-D photo editing so difficult.

Morse, with the help of BYU graduate student Joel Howard and Adobe researchers Scott Cohen and Brian Price, developed an algorithm capable of removing portions of a photograph from an image, much like the current "content aware fill" tools in Photoshop. The editing process could allow software users to remove unwanted objects and blemishes from 3-D photos by sampling the space surrounding the deleted portion of an image.

BYU received the original 2-D process from Adobe, but Morse said applying that method to 3-D proved challenging.

"We wrestled with a couple of different ways to do this," Morse said. "We would come close, but even the slightest defect — when you actually viewed it in 3-D, it jumped right out at your eyes."

The group later realized that designing an algorithm that looked for identical background objects to copy, and that gave preference to things that could be blended on both the right and left side of the image, would achieve the desired effect.

The finished photos can't be printed on paper, or easily viewed without 3-D glasses. For the moment, the editing process Morse described will have to wait for technology to catch up with it. Screens that can reproduce the full 3-D image without glasses are not widely available to consumers, because they require resolutions four times greater than HD television. Should the price of production come down, Morse said he could see stereo screens employed in products such as digital picture frames.

When that day comes, he said, there will be demand for software that can edit in 3-D.

However, several 3-D cameras are already on the market, and some smartphones offer dual cameras as well.

Adobe hasn't indicated to Morse whether the company plans to incorporate the algorithm into future editions of Photoshop, and Morse said he had no inside product information, but it could be a possibility. BYU has maintained a collaborative relationship with Adobe since 1997, when the company used the work of BYU computer scientist Bill Barrett to develop Photoshop's magnetic lasso tool. In addition to lending two of its own researchers to the project, Adobe also funded Morse's work.

Regardless of whether his work makes an appearance in Photoshop, Morse plans to continue researching 3-D editing.

"It's actually very fun, very challenging," he said.