View Full Version : Aura Guru help needed

10-04-2003, 02:40 AM
I know how to cut brushes for video, but can someone tell me how to cut a brush that moves?

example.. I need to cut a brush of object that starts in upper left corner and ends up in lower right corner of video clip.

I try to cut the brush but it keeps cutting video in the same spot for length of video which isn't what I want.

Steve Thompson
10-04-2003, 07:33 PM
Hi Prospector,

Once you've cut out your brush then go to KEYFRAMER and select NEW and if you want you can enter a name or just hit enter. Position where you want your brush to start and set the keyframe (Create Key). Move your brush to where you want it to end (make sure that your keyframe has moved to the end of the timeline) and set keyframe (Create Key). Select all your frames and Hit APPLY FILTER. Not in front of my Toaster now but let me know if you have any problems.

Steve (not the Guru) :D

Steve Thompson
10-04-2003, 07:39 PM

I just re-read your question and may have misunderstood.

Do you want to start cutting out the video in the upper left and have it continue on down the lower right corner as it cuts?

Sorry if I misunderstood!


10-05-2003, 03:45 AM
Yep, I need a cutting brush that moves around as it is cutting.
Can only find way to cut in 1 spot over length of video

Steve Thompson
10-05-2003, 04:36 AM
Ok, How about this. My computer is in the shop now so I'll throw out suggestions until you get what you want.

How about setting up your keyframes in reverse and using the erase function and then play it in reverse as a reveal?

Keep me posted

10-06-2003, 02:21 PM
The CutBrush functions are not animatable. However there are easy workarounds, assuming you just need the "brush cutter" to move, not automatically respond to changes in the scene (which would basically require either keying or rotoscoping techniques.)

So let's take an example:

Say you want to cut out a round brush, starting from outside the upper left corner of the screen, and travelling over time off the screen at bottom right.

Paint a filled circle the correct size for your brush in an empty layer. Pick it up as a brush, optimize it, and set up the move from top left to lower right in the keyframer (over an empty layer the same length as your video clip.) Apply.

Turn on Preserve Transparency. Merge your video clip layer with the circle layer. Select the frames of the circle layer, and pick up the whole screen as an animbrush (or simply export that layer, and reload it as an animbrush if that's really what you need.)

If you are trying to follow a particular object in the source video clip, you can use the pixel tracker if necessary, animating the circle along that path in the keyframer -- or simply set up a few keyframes manually before hitting apply to create the circle layer.

10-12-2003, 04:06 PM
Finally got the computer free (rendering) and tried it..
:D works just as I need it.


now gotta try thr pixel tracking a bit (never worked with that part yet).
Then comes the hard part..
compositing part of a hand (that moves around screen, hence the question about the brush) around a 3D object from LW and keep the fingers wrapped around the object correctly.