Have you ever wanted to edit some video in the VSE and send some of it to the Node Compositor? I have, and I thought you could make a script to do it, someone else thought that too and now you can.
Find the script in this BA thread (version 3 is best): http://blenderartists.org/forum/showthread.php?221567-Edit-strip-with-compositor
At the moment it is not an addon, grab a recent version of the script and place it in the Blender Addons folder. Then open User Prefs and activate it. Remember the strip you send must have a short name too. Like “shot-1″ for example. You run the script, select the strip (or strips if it is a key effect) to send and press the Send to Composite button in the strip properties panel. You can even send stacked strips or a series (end to end) strips! And a new feature lets you setup the shots with a predefined Node Group!
The script will generate a new scene and open a compositor with the right media linked using the correct start frames too! Back in the VSE scene your edit will get a new Scene Strip above the old media strip. Check the tutorial for the right setup so that you can scrub the composite in the VSE (very slowly).
Here is the version that I used for the tutorial: http://blenderartists.org/forum/showthread.php?221567-Edit-strip-with-compositor&p=2236974&viewfull=1#post2236974
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