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cung2
03-18-2005, 11:08 PM
hi there,

relatively new this software and been given a troublesome task of masking out someone in a sequence of JPEGS. basically this guy runs from left to right straight through the shot and he needs to be masked out, how would i go around it?

cheers in advance.

if my explanation is poor then i can host an image as reference.

XanderFX
03-19-2005, 12:36 AM
Trying to get rid of the guy or the background?

artisanfx
03-19-2005, 12:43 AM
if you can give or show more details about this shoot that would be maybe more helpfull to answer your question

show some reference and is the camera static or not ?

jussing
03-19-2005, 02:21 AM
Either way, right-click the footage and choose "new mask".

Then push around the corners of the mask to fit your man. Use the pen tools in the upper right corner of the screen to add points to the mask.

Activate the "clock" button for "mask shape", which makes it animatable.

Then move around the timeline and adjust the mask.

If you want the mask to fit perfectly, use multiple masks so you have one for each arm, one for each leg, one for the body, etc. That'll make it easier to administer all the points as his silhouette changes shape.

- Jonas

cung2
03-19-2005, 01:57 PM
thanks for your replies, ive tried the way you suggested jussing but its quite difficult to do, because the guy is running through an entire sequence.

heres an image:
http://www.imagehop.com/show.php?id=84d0f261b2bf9

http://www.imagehop.com/show.php?id=84d1f2e0d390f

this is a still from a sequence of 120 frames. the guy is running from X to O as highlighted in the image, the only problem is he is running through the middle of the shot which he wasn't suppose to do (as you can see why everyone is either on left or right). because behind him a space ship is going to land, since that is going to be composited ontop of this plate he literally runs straight through the ship which will look quite wrong.

thanks in advance for your replies

cung2
03-19-2005, 02:24 PM
heres a link to the full footage, you'll see where i mean- the sequence where i need to mask him out is 30seconds into the footage.

the entire footage is 35seconds long, the clip is 9mb. the sequence i'm working with is in JPEG's. I don't have an empty backplate of the current shot so i need to find a way around it.

www.chris-ung.co.uk/shot.html (http://www.chris-ung.co.uk/shot.html) (quicktime movie embeded in html webpage)

thanks again.

artisanfx
03-20-2005, 01:09 AM
ok the shoot looks nearly clean

but there is some problem on the end when all people runs away
the man you want to clean will running 19 frames on the end of this shoot in the front of other people
so i mean you can clean the first 89 frames without much problem just using a mask shape follow with keyframes *click twice the layer and shooce from the tool bar the pen and make a mask arround the object * mode select invert to key out just the object and put the layer over a clean background
but the rest u have to rotoscope nearly 19 frames to paint also the people behind from the object and thats the hard part of it

cung2
03-20-2005, 04:03 PM
thats great stuff! thanks i'll give it a bash! cheers for the advice. :)

artisanfx
03-20-2005, 10:22 PM
here just a smal example of your footage
http://www.dreammotion.com/images/back.mov

cung2
03-21-2005, 08:05 PM
you actually had a go yourself!!
thats a really good job considering the material I uploaded was a quicktime file... not the best editing format to work with, but thats really good!

I'm getting very similar results for the first batch of the frames but the remaining section its alot more difficult- but its coming together.

your help has been invaluable! many thanks! :D

XanderFX
03-21-2005, 09:25 PM
I was looking at your video and noticed you would have a hell of a time fixing the people behind the guy unless you remove them too so you may want to think about leaving everyone in and just have them in front of the ship. It will also help to sell the integration to have some foreground elements. You can use the vector paint tool in AE to mask paint in the foreground people or if you have a series of JPEGS I would use photoshop to paint a mask around the people that occlude the ship and then bring them in onop of your rendered cg footage this way you can avoid have the issue of painting out the other people. This way you'll only have to mask a small section of each person as the ship passes behind them.

cung2
03-22-2005, 12:13 AM
I was looking at your video and noticed you would have a hell of a time fixing the people behind the guy unless you remove them too so you may want to think about leaving everyone in and just have them in front of the ship. It will also help to sell the integration to have some foreground elements. You can use the vector paint tool in AE to mask paint in the foreground people or if you have a series of JPEGS I would use photoshop to paint a mask around the people that occlude the ship and then bring them in onop of your rendered cg footage this way you can avoid have the issue of painting out the other people. This way you'll only have to mask a small section of each person as the ship passes behind them.

i was actually thinking about the possibility of doing this, but the idea of image masking over 100 jpegs in photoshop kind of put me of :S. (not too familar with vector paint for this effect as i've only ever used it for animated titles) however this may seem like its a better alternative since masking the guy out in the last set of frames has proven difficult.

need to do abit of research but I will definitely give it a go!
cheers for the suggestion!!

oh if you know of a faster way, please let me know. thanks in advance! :)

XanderFX
03-25-2005, 12:12 AM
Here's a tutorial on vector paint roto http://www.creativecow.net/show.php?forumid=1&page=/articles/oneil_bill/as_matte/index.html

Good luck

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