You can use a crop box to apply DeGrain and ReGrain processes to a specific region of the front clip rather than the entire clip. Because grain management is typically performed when you work with high-resolution film clips, using the crop box can greatly increase interactivity while setting DeGrain and ReGrain parameters.
To define the DeGrain and ReGrain area:
(the crop box does not affect clip processing from the desktop).
The new crop box replaces the previous one. The clip can now be processed from Batch