Is this possible and if so, what is it called?

D

dustinsleeping

Member
Here is what I am trying to do...

I want to be able to literally cut around a person from some footage and use that person over some other footage (similar to green screen stuff). I want to add an effect to the person but NOT have that effect on the footage that I am putting behind that person.

(My film is Black & White but for 1 scene there is a girl who appears in color...but I also want her to have an old film look to her (with scratches and hairs and whatnot...i have Boris CC to this part)...if you just key out the green screen and add the BCC filter it still affects the whole frame...I just want to affect the girl.

How do I do that? And is there a proper term for what i am trying to do?

Does that make sense?

Thanks a million in advance for any tips.

D. Lane
 
It is called rotoscoping. Is a basic procedure for isolating parts of a video and applying any effects to that isolated part.
It can be easy (but really time consuming as you have to rotoscope every frame of the video to isolate that wanted part). I usually use after effect (sometimes I have the chance to use SHAKE that is more comfortable for rotoscoping stuff).

For some really good tips for rotoscoping visit Andrew Kramers tutorial section

http://www.videocopilot.net/tutorials.html

and the basic training for begginers.

http://www.videocopilot.net/basic/index.html

hope it helped
 
Actually that does not look like what I am trying to do.

Let me see if I can explain it better...


I want to take a moving person out of a clip (just the person and NO background) and apply that person to another clip (a background).



Maybe that makes more sense?


Thanks for any help with this.

D
 
if your doing this in AE as i presume since its in the AE forum :), and youve keyed your talent from green screen footage and want the efftect to only apply to that layer, you can create a matte from the keyed footage, and use that matte for an adjustment layer which you can apply the boris filter to. that way the filter should only apply to the matted area where your subject is. but i wouldnt think youd have to do that at all. you should make sure that your boris effect is BELOW your green screen keyer in the order of the effects applied to the layer you are keying, and it should apply after the image is keyed and only to the visible portion. i havent worked with many boris effects before so i dont know if its only an overlay for the entire frame or whatever, but its worth a try to see if it works normally. if its a generate effect it likely generates the effect as an overlay for the entire image, so you would use a matte then, by using a duplicate of the keyed layer with visibility turned off you could try using the duplicate as a ALPHA matte as well. .. sorry if this post is weird. im dead tired ... . signing out. :)
 
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IYou have two options, one by rotoscoping it and the other by greenscreening it.
If you tape the greenscreen footage well it will be easier. there is lots of info in this board take a look and try the greenscreen way. But if you have already recorded the material you will have to rotoscope in after effect (or other software) and put it over the background.
 
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I have already shot the footage (on green screen). Adding the effect before or after I key it still adds the effect to the areas where the green screen is/was. So regardless of the green screen I still need to EXTRACT the person from the frame and add that person to a completely new background.

So.

Is there any tutorials out there on rotoscoping in general?
Maybe a complete training DVD on it or something (I have no problem paying for it)?

Thanks a million for any and all advice.


D

(I have After Effects CS3 by the way)
 
..have you tried using a non-visible duplicate of the keyed footage as an alpha matte for the effect placed on an adjustment layer? - this is a standard way of doing things, and is very quick and easy to do.

..or generating a mask based off of image alpha (use autotrace feature after footage is keyed) for the keyed footage, and use the autotraced mask(s) for the effect on an adjustment layer? - this is a little more complex, but allows for more refinement over the effected area.


..i just really think you shouldnt have to rotoscope since your working with greeen screen materials, and you can already create either an alpaha matte or a fully keyframed mask based off of the keyed footage transparency to use for the layer that you want to apply the effect to so that it only affects the same area as the talent. autotrace is basically an auto rotoscoping tool.. and using a matte would do basically the same thing, perhaps just a little more detaild for feathered transparency within the image.

EDIT: here.

www.rowecine.com/exhibition/autotraced.jpg

ive used the autotrace method in a quick greenscreen setup, and applied the mask to a higher layer and applied a generated cell pattern (instead of the generated boris film effect) to the layer with the autotraced mask(s)...(sorry about the size) you will have to soften and shrink the masks to your liking, but it should wrok perfectly to do what you want to. i added the explosion thingy behind to show the keyed footage. and as you can see, the generated effect is only over the area of the keyed subject, and will stay that way using the autotraced masks. i just switched the effect layers blending mode to my liking to composite it with the keyed talent layer beneath it. or again, you could just use a non-visible duplicate of the Green Screened footage as a track matte for your effect layer based on alpha.
 
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dustinsleeping said:
I have already shot the footage (on green screen). Adding the effect before or after I key it still adds the effect to the areas where the green screen is/was. So regardless of the green screen I still need to EXTRACT the person from the frame and add that person to a completely new background.
Click to expand...
In order to EXTRACT the person you use an effect like Keylight to remove the green.
I'm confused, I'm pretty sure its Neils fault. If you could post a still from the source footage it might be helpful.

I'm not sure what you mean by this:
dustinsleeping said:
Adding the effect before or after I key it still adds the effect to the areas where the green screen is/was.
Click to expand...
Are you adding another effect in addition to keying the footage?

At any rate, if it's at all possible to use Keylight instead of trying to roto the shot that's the route you should take. Roto work is no fun for anyone.
Here's a direct link to one of Andrew's tutes
http://www.videocopilot.net/tutorials.html?id=50
 
milksac said:
I'm confused, I'm pretty sure its Neils fault.
Click to expand...


haha. :) sorry. im not always the most clear. check out my above post that i edited, and it should give you and him a good visual on how to do it. the issue he's having is that since the Boris effect is a generated effect. the effect is generated over the entire footage dimensions regardless of what layer based effect applied transparency is being applied to the layer because the Boris effect is actually being created on the layer IN ADDITION with its own given transparency values for the entire frame. ..so even if the image is transparent in places, the boris effect comes in and creates its own visible alpha values forthe whole frame. so hes got to either mask or matte it to give it an outside referenced restriction that keeps it from generating in the frame where he doesnt want it to by restricing the layers final rendering to only the area allowed by the referenced mask or matte.

..that probably wasnt much more clear, but anyway... hope the above post helps with the image and all.
 
Thanks for all the info. I am still looking into the best way to do this but I will post here when I came up with the results.

Thanks again.

D
 
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