X_Despill v1.2

This gizmo is based on a basic average despill expression, but it adds more flexibility and customization.

Also, it can use a non-destructive method for the core of the matte, in case you only need to adjust the edges.

 This is what the controls do:

• The threshold indicates how much green is going to be cleaned up.
  
  
• The edge strength adjusts the radius around the edges that is going to be affected.
  
  
• The color balance indicates how much green and how much red are going to average against the green.
  
  
• Mix will dissolve between the original image at 0 and the full effect at 1
  
  
• You can also premultiply the rgb against the alpha.