The BCC Composite Choker filter allows the user to contract or expand the edges of a matte to bring them closer to or farther from the foreground. Two Choke controls allow you to smoothly adjust the matte, while Region Parameter controls allow you to define a specific region of interest with which to apply the filter.
[To learn more about this filter, and see a breakdown of the various controls, please click here.](https://www.borisfx.com/helpdocs/?page_id=448 “BCC
Composite Choker Help Documentation”)