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More practical chroma key

Posted: Mon Dec 26, 2005 8:59 am
by chromafresh
I have a request on a topic that was touched on in another thread. Basically there are potential opportunities to use Modul8 to do composition and VJing in a live environment with live video sources. Obviously one could do this without keying, but the potential would be much better with a more effective chroma key.

So whats the problem? Well with the current R/G/B options in the luma key filter, the "range" that is keyed seems very limited, and isn't adjustable. I tried about 3 different cuts and even a 100% Green PSD file and none of them provided a usable key. The best I could get was a with the 100% green file, but even then the backdrop was about 20% opaque.

As an example, theres a manufacturer of outdoor and snowboard equipment who wants us to organize a party next year and we proposed the idea of live compositing their models and musicians, etc. into collaged backgrounds utilizing Modul8... it seemed like a good idea until I actually started playing with the luma key options for chroma...
I know this isn't keying software, understood, but it seems like theres alot more potential for creative expression, for collaboration with live artists, more potential for real time compositing, etc. that could be explored if the key was just a little bit more useful. Please look into tweaking this!

Even a perfect video source will have a black edge running around the outermost edge of the image. A switch to crop this out would be great as well (I'd have to check but I think its only about 3 or four pixels wide).

Re: More practical chroma key

Posted: Wed Dec 28, 2005 3:24 pm
by yves@garagecube
Modul8 2.5 supports chroma keys with tolerance. It also allows you to pick a color directly on screen.

Posted: Thu Dec 29, 2005 12:10 am
by chromafresh
damn. amazing!!

Posted: Thu Jan 12, 2006 1:13 pm
by VJFranzK

Posted: Thu Jan 12, 2006 7:24 pm
by dreamrec

"Chroma key" is missing from the documentation.

Posted: Thu Aug 28, 2008 6:19 am
by Stokestack
I'm trying version 2.5.6, and I searched the doc for "chroma key". Nothing turned up.

Posted: Thu Aug 28, 2008 8:40 am
by deepvisual
its one of the modules

chromakey module

Posted: Sun Aug 31, 2008 3:23 am
by eyeborg
it's great to have the tolerance knob, but it's not tolerant enough, i still get a white edge around my black and white animations when i key out the white.... the edge is just slightly thinner than before. is there a way of modifying the module to be more brutal with the tolerance? and less tolerant too? sometimes i like the white edge but want it to be even thicker. the v4 gives me great thick white outlines by adjusting the white key. the blur knob in the module is nice but blurs all four edges of the whole media too, not just what's being keyed out... otherwise a great module!

:) grete

Posted: Sun Aug 31, 2008 8:44 am
by vanakaru
I wonder if this has the same issues as Sigma6 points to in this tread ... +animation

Posted: Fri Oct 17, 2008 1:58 am
by tolchok
I've also been having issues with keying, it seems even a well-lit green screen with green fluorescent tubes and "perfect" lighting it does not key the whole background, also no matter how I adjust the tolerance knob it either leaves green in the key area or adds transparancy to my live image and fades out my background.

I've tried adding keying filters to key more precisely but to no avail it just renders the transparancy effect even worse...
amber trichomes

Has anyone had any luck with this?

Posted: Tue Mar 17, 2009 11:50 pm
by gmint
I'm experimenting with the chromakey module and so far, the results that I have gotten are marginal, at best. If I'm certain that acceptable results can be achieved, I'm going to invest in a green screen so I can basically drop live video of people into my compositions. However, I could use some advice and/or confirmation that I can achieve reasonably good results. Thus far, I either get VERY blocky masks or, if I turn up the blur, very blurry video (and at least as far as I can ascertain a couple of the controls don't seem to do a whole lot).

Like I said, right now I'm trying to achieve this with little more than a halogen work light and a solid color surface, so clearly I could improve my results somewhat with better equipment and obviously, we're not going for cinema quality results here, but a fairly sharp image with a decent mask is the baseline. Anyone tried/done this successfully? Insight is greatly appreciated!

Posted: Wed Mar 18, 2009 11:39 am
by ilan
I have worked quite a lot with green screen footage. Particularly using KeyLight in After Effects. In any situation if you have a decent green screen and know how to get the lighting right you'll have a good key. Otherwise software will only take you so far.

The people over at Forward Motion Theater had one of these LiteRing and Chromatte systems from ChromaFlex. The results were highly satisfactory. ... /index.htm

Posted: Wed Mar 18, 2009 1:13 pm
by deepvisual
reflecmedia - i just bought one.
close to £3000 for the set though,,,

its a babe.

as for chromakey, no amount of software will pull a good key from bad footage. you really have to light and shoot it right.

Posted: Thu Mar 19, 2009 12:25 am
by gmint
Guys, thanks for the tips, that was some really great info! The reflecmedia kit looks awesome, but it's much more than I'm willing to spend for this particular application. Nevertheless, I have a clever idea about how I may be able to duplicate their setup. That said, I do have some further questions. I wasn't very clear about this the first time around, but specifically with regard to Modul8, how good is the chromakey module? I mean, I'm going to assume that it doesn't rival that Ultimatte DV box from reflecmedia, but assuming I am able to get a good green/blue screen setup with correct lighting and such, what are the results going to be like?

I know that's a really difficult question to answer with any degree of certainty, but what I'm asking is, can it generate an image that's going to be at least usable? Again, I'm not looking for cinema quality. As a point of reference, if you've seen the keying that iChat does (to insert funny backgrounds), can I get something equivalent to that? [on a side note, I'm actually pretty impressed with how good of a job that iChat can actually do at that, especially considering that it does it basically automagically with the crappy iSight camera].

Posted: Thu Mar 19, 2009 10:30 am
by The Midi Thief
Take a look at Q@mera from b-l-a-c-k-o-p. They do the keying thing with iSight/iChat but can also be used with Modul8.

I once saw a demo of somebody doing something with q@mera and Modul8 but I've lost the link and can't find it again. The blackop page says that q@mera is compatible with Modul8 however.