cf/x has released a suite of inexpensive, pro-level plug-ins for iMovie. this is one them.
color exchanger is a plug that targets one color and exchanges it with another. you can allow some "leeway", i.e. tell the plug to also target similar colors. If you use similar colors, the plug can also introduce the same 'difference' to the output colors (i.e. make the output color similar in the same way the original was).
this plug comes with all standard cf/x plug features:
- specify area of effect (i.e. you decide which part of the clip is affected) and
- pick effect colors directly from the clip.
all plugs can be downloaded for free and are fully functional. those plugs that must be registered put a reminder of that fact into the clip.