...You can apply other filters to one area using a mask, then apply other mods to a different area using another mask, and so on. The original had, in my opinion, confusing options which mixed the current frame with saved frame B and applied the mask to frame B. The current version mixes the masked current frame with saved frame A.
To enable this filter:
Move fblenderM.vdf to the plugin folder for virtualdub.
To use it:
1. Add "filter blenderM" in your virtualdub filter chain. This first instance must be to Store the current frame to A
2. Then add the filters you wish to modify the video.
3. ...