Tuesday, July 14, 2009
Eliminate Camera shake on your movies.
Wobbly Cam may well become a thing of the past.
The kind of shaky handheld footage that is a hallmark of amateur movies has become popular with Hollywood directors in recent years. But new software means that handheld cameras need no longer give wobbly results.
Computer scientists at the University of Wisconsin, Madison, and software giant Adobe have developed a technique that mixes 3D reconstruction with optical illusion to turn distinctive wobble of handheld camera footage into the smooth glide of a Hollywood tracking shot.
The process starts using off-the-shelf software called Voodoo Camera Tracker that can reconstruct a camera's path through 3D space from a video sequence.
Using that as a reference, the software then tries to distort each frame to create the way things would have looked were the camera to have been on that perfect, smooth path. Rather like a fun house mirror, different regions of each frame are warped by different amounts.
That distortion can be apparent when frames are examined individually, but when run in sequence, the brain thinks it is seeing footage taken from a camera moving on a steady path through space.
Existing 2D stabilisation techniques, sometimes built into video cameras, can reduce the effects of camera shake, but are limited by having no way to read a camera's path through 3D space.
Attempts at 3D stabilisation have in turn been hindered by the fact they make each output by combining multiple output frames, resulting in "ghosting" of fast moving objects and people.
This isn't a problem for the new technique because it distorts each frame in isolation, instead of combining multiple frames.
New scientist july 12th 2009
Posted by asking questions at Tuesday, July 14, 2009