Use the Edge node to do one of the following:
         
         
            - Create a greyscale image composed of
               the edges in an image. You can apply edge-detection to both colour
               and monochrome clips.
            
- Modify the edges of the key. You can
               apply the Erode, Shrink, and Blur filters to the edges of the matte. 
            
The Batch Edge node is
            the same as the Modular Keyer Edge node. See 
                     Edge Node.
         
         NoteWhen using the Edge
               node, values for blur width and height, and shrink and erode width
               will be scaled following the current resolution of the node. Switching
               an Edge node input from a PAL clip to an HD clip will update the width
               and height values automatically.