By Michael Burns | on May 22, 2006
Moujou is a matchmoving plug-in for Maya from 2d3. It takes its functionality from Boujou, the company’s popular standalone matchmover. Like its sibling, Moujou allows automatic tracking of elements in footage to acquire camera data for use in VFX work.
This data is used to create virtual 3D cameras with the same rotation, focal length, and position as the real thing. These virtual cameras allow you to render CG objects in 3D packages, before compositing them into the original footage.
Moujou works in two stages. The feature-tracking stage analyzes each frame of the sequence and tries to find areas that stand out from the surroundings. It then tries to match these reference features from one frame to the next to build up a set of 2D tracks. This is followed automatically by the camera-tracking (or solving) phase, which uses the 2D tracks to work out how the camera moved in 3D space, and the 3D positions of the 2D features.
Moujou allows you to add an interactive element to this automatic tracking phase through the use of mask images. These screen out extraneous information that might cause a confusing result. Or, you can use a mask to isolate a moving object from the background.
An appropriate camera type will be selected based on the resolution of the images, such as PAL widescreen from a resolution of 720-x-576. Animation options control what is actually tracked – for example, you can set whether the camera rotation is to be mapped and whether the reference objects in the scene are static or moving.