putting a sign on the side of a vehicle

[Nick Jushchyshyn]

As a professional matchmove artist who works on everything from indie films to TV commercials to feature films .... I just want to chime in to back up what's been said so far. .... printing a sign or banner or something at Kinkos or Staples or anything like that and using magnets to apply the sign to the van will be FAR more effective and less costly than learning tracking as you go.

Imagineer Monet is an application that is dedicated to this type of work, but go check the price of that and you'll find the printing costs are far less ;) (plus you don't have to learn tracking.)

There are several matchmove applications that will happily track your car in 3D (SynthEyes, Boujou, MatchmoverPro, PFTrack) ... but prices generally start at several hundred dollars and range up into the thousands depending on which app and feature set you choose. ... and that doesn't include that you would still need to export the results into a 3D app to render the sign for compositing (though I guess 3D for a flat sign can be done in most compositing tools these days).

Anyway ... looks like you're all set to go with a magnetic sign.
(Might want to check with local sign printers. They can often print large format magnetic sheets that will look a lot better than a paper sign stuck on with little magnets.)

Good luck.
Have fun.

[Jim Andrada]

I second the vote for a sign shop making a magnetic sign. Little magnets will probably fall off if air gets between the vehicle and the sign itself. At the least the paper or whatever would flutter and the magnets would be visible in the picture.

There might also be some films that are printable and can then be adhered to the vehicle - just guessing.

Real Estate agents etc often have these magnetic signs because they can put them on the car during the day and take them off when using the car for personal use.

By the way, unless it's a big boxy truck, the sign will likely not be a plane when it's on the vehicle as side panels etc are usually curved. Getting a curved 3D surface of the same shape as the car door or whatever isn't so terribly difficult, (drill holes in a grid on a piece of plywood and stand it up close to the surface and poke dowels through until they hit the door, then measure them and loft the surface in something like Rhino and export to your package of choice and project a sign on it as a texture).

But if the surface isn't a plane, I'm not sure AE etc can do much with it so you'd be into a really interesting exercise in tracking the vehicle motion and exporting the motion path and having your 3D package fly the panel around, light it properly in the 3D package, make sure it's believably textured with some dirt etc etc etc. and render out a video and then try to match it up with the real video --- aaaaaghhhh! To say nothing of having to have proxy geometry as texture catchers for anything between the camera and the truck so the sign would get occluded at the right spots.

Actually, sounds like kind of fun to try and make it all work

By the way, I did check the price of Monet - seems pretty reasonable for something like this. (around $4000) Pretty comparable to a full blown copy of Cinema 4D with all the modules and a few plug-ins, maybe a bit cheaper than a full Maya license.

[Emre Safak]

Originally Posted by Jim Andrada

By the way, I did check the price of Monet - seems pretty reasonable for something like this. (around $4000) Pretty comparable to a full blown copy of Cinema 4D with all the modules and a few plug-ins, maybe a bit cheaper than a full Maya license.

Monet is a specialist tool for object placement. It is not a 3D renderer like C4D or Maya.

[Jim Andrada]

Hi Emre!

I know - I watched all the demos on the Monet site. I was just trying to comment that pricewise it isn't out of line with the kind of $$$ one has to pay for higher end 3D CG packages, and to do what the original post asked you would probably need a suite of tools each one of which was in this price range. Makes the Adobe CS3 Production suite look like an absolute steal!

By the way, the demos seemed to have been shot so this kind of replacement would work well - I noticed that in the demo with the bottle the motion was such that all the motion was pretty much in a plane and around the axis of the camera lens, so curvature of the bottle wouldn't be a problem. If you were taking a shot of a minivan driving past the camera, as it got off to one side of the camera position or turned a corner, the curvature of the side would become obvious so a planar sign might look like it was tearing away from the vehicle. Might be able to make it work in 2D by "morphing" the sign though.

[Simon Sommerfeld]

I agree 100% with the advice to use a custom made magnetic sign (two actually, one for each side of the vehicle). I just did a 2 day B-roll shoot for a low-budget feature using these on the side of a van . They were absolutely worth the up-front cost. Much cheaper than post production fx work.

Best,
Simon.

[Jim Andrada]

OK, now that I've convinced myself that this is impractical to pull off in post, I may be talking myself into thinking that it could be done a lot more simply than I was thinking.

I still am of the "use a magnetic sign" opinion, BUT, in fairness to the spirit of the original post, I'd like to think up a practical way to pull it off.

What I'm thinking is that if you take a bunch of sticky dots that are big enough to see clearly in the video, and stick them to the vehicle in a regular grid covering the area where the sign should go, as the vehicle moves and turns, the grid will deform accordingly.

If you could use the grid points as control points for a 2D morph, and warp the image of sign under the control of these points, then the deformation of the sign should match pretty closely with what would happen to a real sign.

I know that programs like Morpheus Animation Studio let you use a collection of points to control the warping of an image. They say that the morph can be driven by such points and by a series of key frames, and output as an AVI.

Whether programs like After Effects have any such capability or not, I don't know, but I think there are some 2D animation packages that might have similar capabilities.

You'd have to be really careful to not let anything get between the camera and the vehicle while taping, but if you could control the environment of the shot carefully enough (or mask out offending objects) this might all be do-able.

The devil is always in the details, and since this isn't the kind of thing I do myself I don't know enough of the details to be useful, but conceptually it seems like it should be possible.

Comments?

[Nick Jushchyshyn]

Originally Posted by Jim Andrada

OK, now that I've convinced myself that this is impractical to pull off in post, I may be talking myself into thinking that it could be done a lot more simply than I was thinking.

I still am of the "use a magnetic sign" opinion, BUT, in fairness to the spirit of the original post, I'd like to think up a practical way to pull it off......
...
......The devil is always in the details, and since this isn't the kind of thing I do myself I don't know enough of the details to be useful, but conceptually it seems like it should be possible.

Comments?

Yup.
Most compositing apps these days, including AE & Shake (even Motion now), have built in tracking and corner pinning tools that could pull something like this off, especially if you feel like investing in extra frame-by-frame pixel pushing time to really eek out more realism. There's also Monet and the list of several 3D tracking options from my earlier post.

Really, if you already have the tools AND experience to work them, this is truly a routine post-production task that's employed in MOST national level TV ads, network shows and movies (even most high-end corporate video too).

It's just not the kind of thing you want to be learning and experimenting with when you've got a low budget and a deadline looming. Under those conditions, it's exactly the kind of thing that can completely wreck a production.

[Jim Andrada]

I couldn't agree more - don't try this kind of stuff when you're on a schedule and you haven't done it before.

I was aware of the tracking and corner pinning tools (although not experienced in their use) but I never thought they could handle the non-linear deformations that you'd see in a regular grid on a curved surface as it moves and rotates freely in space and apply those deformations to an image.

[Peter Ferling]

Good points so far. However, what resolution are you going to shoot this in? Any noise, shift in pixels, and glare is going to require rekeying. You'll litterly track this on a per frame basis. You would have to shoot in manner convenient for the track.

I have lightwave plugins that can do this, and almost carpel tunnel using digital fusion.

The magnetic approach is good, even painting the thing for the shot, and repainting after is cheaper. You should only get these kinds of jobs as an after-thought, when the production has wrapped and producer is in fits in doing whatever it takes to correct his or her oversight. When the real answer should have been to reshoot!