alternatives to green screen

[Cory Mitchell]

Hey All,

In my never ending pursuit to replace the need of green/blue screen (including looking up those real-time depth cameras) I had an idea that would use a focus assist type system, the kind where if something in focus is highlighted or something like that. Does anyone know if it would be possible to output a focus matte? (like metadata)

Does anyone else have any other ideas that could pull a key without a colored screen? Could a seperate camera be used?

thanks

visionmind

[Chris Kenny]

Some films are using roto extensively instead of chromakeying. This isn't very practical for indies, though, as it's extremely labor-intensive.

There's already software which can do optical tracking and take a fair bit of the work out of roto. Machine vision technology is advancing pretty fast, and in five years there might be software which does pretty good roto without much human help, but we're just not there yet.

[Mark L. Pederson]

Some films are using roto extensively instead of chromakeying. This isn't very practical for indies, though, as it's extremely labor-intensive.

There's already software which can do optical tracking and take a fair bit of the work out of roto. Machine vision technology is advancing pretty fast, and in five years there might be software which does pretty good roto without much human help, but we're just not there yet.

We use MOTOR - VERY powerful tools for roto -

http://www.imagineersystems.com/products/motor/

you can download a free trial version -

[Cory Mitchell]

I've checked out motor (and every other program I could find) and it seems that software could prove very helpful in the automation of the matting process.

What about any hardware solutions? (using two cameras somehow?) or other new ideas to create mattes without a greenscreen?

visionmind

[Jim Arthurs]

What about any hardware solutions? (using two cameras somehow?) or other new ideas to create mattes without a greenscreen?
visionmind

You could use a blue screen instead of a green screen. :)

Just joking, I know what you're asking, and the bottom line is it simply isn't possible to do anything that would be remotely considered "film-quality" in terms of a key. Semi-transparency would completely fail in something that uses depth information even if it was perfect in every other way.

[Bruce Allen]

If you look at the history of film, a lot of things have been tried.

Hitchcock even examined a lot of crazy options (eg shooting simultaneous infrared, etc) back when he was shooting The Birds...

So yes, you could:
1. shoot greenscreen
2. shoot sans greenscreen and use roto, maybe combined with sophisticated guided image analysis / difference matte software
3. get fancy and try and shoot simultaneous infrared or something
4. along those lines, lidar...
5. shoot stereo (or many angles, even) and develop an algorithm to use stereo info to assist your roto
6. use a very high-fps system (with synchronized strobes, etc) combined with high speed cameras and optionally, fluroescent paints ;)
7. Combining #2, #5 and #6, do a multi-cam motion capture system and map out actors in moving 3D space...
8. Combine all of the above!

Personally, I think we should maybe just teach tribes in Africa how to roto, pay them in dollars and everyone wins.

Of course, roto is a skill. Sometimes it requires considerable figure-drawing ability as you are essentially creating a human-shaped outline from a dull blur.

Cheers

Bruce Allen
www.boacinema.com

[Jim Arthurs]

Don't forget the Disney dual movement sodium-vapor process used on Mary Poppins. 'Course they could only make the one beam splitter that actually worked for passing the narrow yellow band of light...

[damonbots]

Dammit, Jim!

You've got me wondering...
What is the Disney dual movement sodium-vapor process?

[Chris Kenny]

Personally, I think we should maybe just teach tribes in Africa how to roto, pay them in dollars and everyone wins.

Maybe you're making a reference to this, but... I listen to This Week in Media every now and then, and one of their regulars does work in Zimbabwe. Apparently what you describe is essentially happening.

VFX houses had the idea to farm this sort of thing out to India a few years ago. So much work has gone there now, and it has gotten so good, that it's barely cheaper than the work in the US.

[Bruce Allen]

Maybe you're making a reference to this, but... I listen to This Week in Media every now and then, and one of their regulars does work in Zimbabwe. Apparently what you describe is essentially happening.

VFX houses had the idea to farm this sort of thing out to India a few years ago. So much work has gone there now, and it has gotten so good, that it's barely cheaper than the work in the US.

I am from South Africa. When the government telecommunications monopoly that is screwing everyone over and keeping us on dial-up finally dies, our VFX industry will really have a chance at taking off.

However, being in LA now, I understand that there is a good reason that many, many things will always stay local.

Bruce