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Hello,
Im a post grad with BA in 3d Animation. I am currently working on a demo reel for 2d/3d Enivronment creations such as matte painting that utilize projections and foreground 3d objects. So with that in mind I decided I would create shots that would emulate what comes down a film pipeline. So I decided I would purchase some HD footage from Artbeats to use for my plate. My thought would be to camera track in boujou (which has its own issues at the moment.) Create a maya output, model the environment in 3d using the track as reference. Then rendering the model and some passes create a final matte painting for the shot and composite the foreground of the original footage and key out the background and replace it with a projected matte painting with some animated elements to sell the shot.
So…. here is my problem at the moment, Ive got the footage but there is alot of motion blur. And luminance keying (my original plan for removing the background) is not working since there isnt much in monochrome variation. So I tried using primatte and doing a quick color selection on the average blue in the BG. It seems to pull a better key then the luma but still very dirty and before I fuss with it to much I want to see what some more experienced shake compositors would do. Im trying to avoid roto as much as possible though I know I will not completely.
Here is a still of the shot (its a 1/2 proxy) Thanks for any help with this.
There’s a lot of compression on the proxy image but I got a reasonable key off the foreground leaves (orange, yellow keys). Then its just a matter of filling in the holes with a loose mask. Would that approach work for you across the length of the shot?
I think there is a better way to do it than to try and pull a key straight out of the image. If you look at the colour channels, there is almost no blue in the foreground but the background is still covered with that blueish environmental haze. I tried this two different ways and got some good starting results.
Reorder – bbbn > ContrastLum – val 3.2 > Blur – (box)20pixels > LumaKey – loVal 0.174, hiVal 0.326 > DilateErode – alpha -1 > Invert-alpha > Switchmatte
and:
Reorder – rbbn > DilateErode – red +1 > Blur – (box)20pixels > Keylight (on the red leaves) (.6602, .2573, .2573), screenRange .0756, shadowGain 1, midtoneGain -.217, highlightGain -.070, midTonesAt .671 > Lumakey – loVal .185, hiVal .4 > Invert – alpha > Switchmatte
This is all the important info, I just hope it is legible. These both worked, but the second one was a little more to my liking. There is still some work that can be done to them, and some roto you might need, but this does a pretty good job I think. But if anyone thinks I have my head up my arse, just tell me straight. I’m new at this too and I know that there is usually a better, faster way to do these kinds of things. I just hope this helps.
The proxy is pretty compressed yes, its just one of the 700 or so images from a boujou proxy, the original has better quality and higher rez 1080p from a Sony HDC-950. I was thinking of using the blue to my advantage but I didnt think of your way so I will drop it into shake when I get home from work tonight and will let you know.
Hi.
There is another way. Try to key the foregroung trees and not the background.
First remove a little bit of noise and grain using blur (10 px x 10) and a median filter (default setting). Use Primatte for pulling a key on foregroung trees. You have to set many foregraung/background operator, about 10.
Finally blur a little bit the generated matte. In still is quite good, but key must works in animation… try anyway 🙂Good work at all!
I will try all you suggestions and get back to you.
The only other thing that I could think of would be to make a matte from a still and do a camera projection onto some geometry. I’m not sure if that would work for you or not–it just might give you the right look.
–tough pull though. 🙂Well Im going to run the shot thru boujou and alot of the bg area will be reprojected back onto geometry in maya but Im creating a matte that will extend above the shot’s top and the foreground trees will drop down, to reveal the matte area. Basically I just need to key the edge of trees from the fg to bg so I can cleanly edit without having to roto the heavily blurred frame, I can easily throw in a garbage mask where the keying doesnt work on these edges. http://www.artbeats.com/prod/clipinfo.php?id=13994&fr=search&pg=1&kw=FCA121H2&ct=&fm= to see the video of the clip. I will edit the camera in shake to fly higher revealing the 3d in the far background.
Well I think Ive got it, that last example works rather well, though I will need to garbage out some stuff but for the most part the edge of the tree line is intact. Thanks for the help and I will post the final sequence when it is finished for you all to check out.
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