You can build this in Quartz Composer and send the video over Syphon using the QC Rehab trick.
There is an example of video delay you can download from the web.
I don't know if you are familiar with QC? These are the tools you need:
- Quartz Composer from Apple (it's free and on you Apple developer DVD or register as an developer and download from Apple's dev site).
- Bangnoise's Video Delay patch for QC. Download here and look at the example comp after you've installed the patch: http://kriss.cx/tom/video-delay/
- Dowload and install Syphon plugin for QC from the Syphon site:
- Follow my tutorial on how to install QC Rehab and make syphon input in Modul8 possible: http://themidithief.com/2011/06/syphon-input-in-modul8/
- Open Bangnoise's Video Delay example comp in QC. Add a Syphon server. Draw a patch cable from "image" on the Video Delay box to the "image" on the Syphon server box. Give the Syphon server a name (use the inspector, look under "input parameters".
- Go to Modul8 and load the "Syphon Client QC.qtz" file that came with the Syphon QC plugin. If you see an image from your iSight with two delayed sections in the QC output window, you should also see the same thing in Modul8 now.
- Now modify this into what you wanted. You can have other video input than your iSight of course. Now you're on your own.
If you have already launched the iSight in Modul8 before you started Quartz Composer this will not work. Shut down M8 and QC and launch QC first and make sure you see the iSight input. Then start M8 and load the "Syphon Client QC.qtz".
.... and by this time Deepvisuals would have come up with a much simpler solution that takes 2 seconds. But seriously, it took me way longer to write this than to make this example work on my MBP.