Rotoscoping Lightsabers on Interlaced Video
 

What would be a good way to rotoscope lightsabers on interlaced video? Should I try to deinterlace it first and then rotoscope in Photoshop, and then reinterlace it? I would like to preserve the 60i framerate though. Can I rotoscope using the interlaced frames (with all their jaggies) and then just import it back into the video editor?

Hi there,

roto work is hard labour at the best of times - usually a last resort in any compositing situation. If you can't separate out the blades by any other means (a luma key springs to mind) then yeah, de-interlace your footage the best way you know how, (avoid interpolating the fields - you lose half your data - try a merge fields or duplicate fields), and then get to work. But I would also strongly suggest doing the roto work in a compositing app like digital fusion/combustion/after effects. Doing it in Photoshop will be like pulling your teeth out with pliers and then rinsing with a lemon juice mouthwash. Not good.

best,

David.

Here's how I would do it:

Export an AVI or QT of the 60i footage to have the roto work laid on top.

Use Particle Illusions SE (download the "lightsabers" library, all from wondertouch).

Set the footage as the background, do the lightsaber effects.

Once you like it, remove the background 60i video, turn on motion blur, export as a TGA sequence with Alpha and black edge removed.

Import the TGA sequence with alpha and lay on top of the original video in your NLE, whether it be Avid, Premier or whatever.

Viola, wicked ass lightsabers.

PS - the PI lightsabers library also includes the "hits" where the sabers clash, very cool.

Now if you really want rotoscoping and not just lightsabers, I probably just wasted your time and can give you some ideas on that too, but I think this is what you want to do. All in all, for 100.00 you can have lightsabers every bit as good as Star Wars with only about 2 days practice...

Here is a link on how to create just about every Star Wars Effect you want.....

http://www.theforce.net/theater/tutorials.shtml

Scroll down to the section labeled "Adding Lightsaber Blades to Pictures and Films."

Yes, you will need to de-interlace your video footage when rotoscoping. It's very difficult to do while interlaced.

There are a lot of ways to do it, I looked at the above link which has some really cool ideas that are all valid, and all many times more difficult that using particle illusions. No deinterlacing required. I strongly suggest you look at this idea as it could be so much more difficult than it needs to be...

Hang on,

I think I got the wrong end of the lightsaber on this one so to speak. Are you rotoscoping OUT lightsabers from a piece of footage - or are you ADDING lightsabers to your footage? Rotoscoping generally refers to separating out an element from its background. If you are just adding them to the footage then the above suggestions are right on the money.

David.

I'm putting in the lightsabers. I've used the technique described on theforce.net before but never with interlaced footage. Without doing it at 60 fps, the interlaced footage has interlacing artifacts and I can't imagine that's the right way to roto the lightsabers. And I don't have the expertise to use all the particle effects. I think I will deinterlace and roto with a filmstrip like I always do. Thanks a lot for all the suggestions.

Do you have After Effects?
If so just take your footage and change the interpolation of the footage.
goto www.dvgarage.com They have a great site there that always deals with these types of questions.


Rob:D

Alamdv (www.alamdv.com) is a simple way to do it. I'm not quite sure but I think the de-interlacing is done for you. Basically you import the video to Alamdv and then using the plugins that they already have for light sabers, pick the color you want, add the effect to every frame (not fun) to coverup the original sword and "fit" the effect. Save the project and insert to your NLE. The problem with ALAMDV is that it does not import audio so you would have to sync your audio and video at the NLE level. Oh, the best part is that it is cheap #49.99 or ~$89.00 USD.

I have done lightsabers with 60i footage and it sucks real bad. I never found an easy way of deinterlacing the footage. I always got a blurred effect to the whole clip which is not what I wanted in terms of quality. I'm sure if I played with it some more I could get it but I just shoot everything in frame mode now. My instructor has told me a way to shoot in 60i and import the footage into after effects at 24 fps or at least it looks that way. I'm going to be trying this very soon and I will let you know how it works out for rotoing.

Take the composition settings and set it to 60fps. Then when you export again set it back to 30fps.

Otherwise you can follow the cinealta tutorial for bringing in both fields seperately then overlaying one and low its opacity...short end of the stick. There is way more info in that tutorial that is interesting to look at and try.

Rob:D