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Mechis
02-11-2006, 06:09 AM
Hi!

I recently saw a video of people dancing around, but their hands and head were rotoscoped out... so it looked like just the clothes were dancing. What amazed me though, was that you could see the back of the clothes... so if the shirt was unbuttoned, you saw the back of the shirt... or if you looked up the sleeve, you saw a hollow tube where the arm would be.

Does anyone know how the artists were able to comp in the backs of the clothes?

Thanks,
~Mechis

evanfotis
02-11-2006, 01:48 PM
It would be nice to give a link to that video if there is one.
On top of my head, this would involve several layers comping if using only AE.
Lets say that the top layer1 is the clothes only layer(keyed/masked footage).
Underneath, layer2 could be the same footage layer, with only the external parts masked, with animated masks, and used as a track matte for the innards of the clothes on a lower layer3 done by either stamp tool or other technique.
Needs a lot of tweaks and cheeting, depending on the footage.

Mechis
02-11-2006, 02:49 PM
http://www.freakydeke.com/demo/commercials/Louguan_commerical.mov

This is the movie.

I'm not sure I understand your description. The problem with Layer2 (mask the external parts and not the internals) is that the person's body is going through the clothes so you can't see the inside of the clothes... That's what I can't figure out.

Thanks,
Mechis

evanfotis
02-11-2006, 05:06 PM
Wow!
Multiple Masking Galore...

Probably the dancers where wearing those skinsuits or painted all green or blue without shoes.
After filming, in the post ,they keyed it and added image from where body overlapped the clothes, plus removing the clothes insides at their ends.
Filmed with high contrast to through shadows in the orifices, so there's less to see and more difficult to tell where it has been painted.
Gotchas:
Note in 4sec and in 6 sec where the arms overlays the body -and the fun begins- the shadow of the arm is still present.
In700 the trouser bott is a bit too round
Look also at 15sec where a mask starts clipping the trouser up right on screen!
At 17 sec you can see for a frame the back of head which then d.issapears(mask came in late) and the head looks choped more than in should.
At 22sec motion blur is tough to mask.

You get the message...

In an commercial like that where $$$ is spent one can do many things and use many people.

nateomedia
02-11-2006, 06:48 PM
Interesting observations. I'm an AE newbie myself so I found those call-outs very helpful. After you called it out, I started looking at the shadows throughout the commercial and you can see where the feet and heads were -- they didn't even attempt to mask them out. Thanks.

Mechis
02-11-2006, 10:35 PM
I can see what you're saying about making the insides of the clothes darker-- like in the sleeves, etc. However, there are some really great details-- ex. at 5sec, you can see the label of the shirt and it tracks perfectly with the shirt.

While the darkening of some areas helps a lot, they still show the inside of the clothes in a lot of shots too. Do you think they painted those areas? I just can't image that they would be able to photo the shirt and somehow comp it in with the footage...

~Mechis

ps. Those errors you caught are really interesting. I never would have noticed them if you hadn't pointed them out. Good eye!

beaker
02-12-2006, 03:09 AM
The commercial was for a Chinese clothing company(shown only in china) about 3-4 years ago. Budget was zero. It was shot, edited, cgi, etc... everything in like 2 weeks. There was some cgi for the collars and insides of the pants, etc.. A lot of it ended up being painted on the inferno.

If I had the chance to do it again on that schedule, I would have skipped all 3d work and 100% painted it all from the beginning.

Funny thing(not cgi related), none of the clothing on the models is actually clothing that the company actually sells. It's all Gap, Bannana Republic, Van Dutch, etc... The people from the company had no concept of using clothes they actually design for a clothing commercial.

Mechis
02-12-2006, 08:19 AM
Thanks for stopping by, beaker. Do you (or anyone else) know of any information (books or internet sites) about painting for compositing?

Thanks,
Mechis

beaker
02-12-2006, 11:06 AM
None that I know of. The thing is it is pretty basic, doesn't really warrant a book just a tutorial.

Depending the shot. If your good enough it's just a matter of hand painting frame by frame but keeping it consistent so stuff doesn't jump around. Also another way is painting a clean plate and then tracking/warping/roto that on top of what your painting over to fit. With both methods, add grain.

Mechis
02-12-2006, 11:44 AM
Thanks for the info Beaker.
~Mechis

evanfotis
02-12-2006, 11:57 AM
I wasn't refering to this commercial when I mentioned $$$. It was a general remark...

Also, even though I spotted some frame "mistakes", these go completely unnoticed when the vid plays realtime, so most of the time its not worth spending extra effort and time to fix minor stuff that average viewers won't even notice.
For Hollywood films, things get a bit more detailed attention:D .
As for resources, the production diaries of KingKong have some episodes on roto and masking.

crutch
02-12-2006, 03:11 PM
Here's a link for you that may be of some interest- http://effectscorner.blogspot.com/I think I found the link posted by Salatar on vfxtalk.com

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