Auto Stabilization


Released in Autodesk Flame 2009


Regular movie clips shot with a film camera have usually a small jittery motion due to the instability of the mechanism passing and fixing the celluloid strip. This motion is very subtle, but stabilization in post is often a requirement. In case of a hand-held shot the shake of the image depends on the camera operator's movements. Sometimes we need to stabilize, or "lock" some very small, high frequency motion; and sometimes we need to keep the general movement of the image by only filtering out the small jitter. The auto stabilizer tool introduced in Flame 2009 (as a batch node) - based on technology developed by me and lot of coding from my friend Eric Desruisseaux - is capable to do all these, with minimal user input.

flame automatic image stabilization in batch
The "classic" stabilization of removing the high frequency, jittery movement. Video.

The algorithm analyzes the clip frame by frame and reconstructs the original motion. The target motion is defined by the user: we can "lock" the images eliminating all movements, or simply smoothing the original motion curves. The operator only needs to define the "smoothing factor" and the adjusted motion channels (translation, rotation and scale). It is also possible to specify the region of interest if we don't want to process the complete frames. Some videos of the tool can be found here, choose the "auto stabilizer".

autodesk flame perspective stabilization
Perspective stabilization, where we track the motion of a 3D planar surface. Video.

While usually only 2D transformations are stabilized, our tool is also capable of stabilizing a flat surface moving in the 3D space. That means we can track a planar surface, and apply a correction to all images such that the surface appears to be still. Other than creating funky effects (check out the example video), it can be used to apply graphics or any other element to planar surfaces in the scene (as a special kind of tracking).