Tracking Using SmartVectors

NukeX and Nuke Studio's SmartVector node produces faster, more accurate tracking data by calculating pixel motion between frames. You can connect a SmartVector node directly to the GridWarpTracker node or write motion vectors to the .exr format, which are then used to drive the warp to reduce overheads later on.

SmartVector data is either calculated in context or baked into the .exr format and piped into the GridWarpTracker node to drive the grids.

Note:  SmartVector data can be written out to .exr files and used in vanilla Nuke, you don't have to calculate the vectors in context. See Generating Motion Vectors for more information.

Calculating vectors in context.

Pre-baked vectors.

Calculating the vectors in context allows you to adjust the SmartVector settings as you go, but using baked vectors is much faster.

To track the grids using SmartVectors:

1.   Click the Track Backward or Track Forward buttons above the Viewer to analyze the whole sequence,

use the Range buttons and enter the required frames to track only a certain frame range, or

use the Frame Backward or Frame Forward buttons to track a single frame in either direction.

2.   Click Stop , to cease tracking in either direction.
3.   Click the Clear Backward or Clear Forward buttons to remove all keyframes in the specified direction from the current frame.
4.   Click the Clear All button to remove all keyframes.

The grids follow the specified feature automatically, using the vector information to move the individual points in both grids.

On simple shots, the grid should be accurate enough to use for warping or morphing. See Warping Shots with GridWarpTracker for more information.

For more complex shots with rapid movement or rotation, tracking might slip causing the grid to deform. Have a look at Correcting Grid Deformation for more information.