Live Chroma Keying

[win101]

I want to chroma graphics on top of live video. What kit can you use ot do this. I know arkaos does this but apparantly it is not very good and you cant just overlay names of speakers etc. Any idea what can be used.

 

Thanks

[mac.calder]

Most vision mixers have some form of decent chroma keying. Or you can buy a chroma unit. I would not use a PC for live work.

 

As for text overlays, you can buy a cheap titling unit for very little $ on ebay if money is a problem. You could also get a chromakey/vision mixer/titling all in one unit - a linear editing suite for a couple of hundred (cheap) all the way up to a tens of thousands for top of the range.

[paulears]

You don't chroma graphics normally, just a simple luma key does the trick. You can use chroma key - and either select the key colour as your background graphic colour or change the graphic background layer to a suitable key colour.

 

Panasonic mixers, and others have reasonably decent chroma and luma keys on the 50/70 ranges, but the old MX10 that often pops up on ebay could do pretty good simple luma keys for graphics, titles, mono logos etc.

 

Chromakey from live sources, even composite isn't normally a problem - as long as the lighting on the background is even. DV colour compression means that green as a key colour is better than blue. Most edit software has keying built in, although off-line software dedicated to this kind of this worls better, especially vector keying which is kind of like chromakey, but lets you have shadows, and key through things like glasses of water, which are really problematic normally.

 

If you want to cut just a couple of cameras and overlay titles, then the mx10 and 12 are pretty good bets if you can find one. The only snag? You need to get composite video out of your computer, not vga/xvga etc

 

Just noticed that this is on ebay now - currently £180

[kitlane]

Is there likely to be lip-synch issues? You mention putting names on images of speakers. If the audience is in the same room then a PC with Arkaos etc. will be virtually unusable. Even a hardware keyer may introduce a delay. FOr example, my Panasonic WJ-AVE5 introduces a 40ms (1 frame) delay even without doing any effects or keying.

[peternewman]

This has definitely been covered before (have a search and I'm sure you'll find some old threads). But anyway if you're at the lower budget end of the market, have a look at some of the Edirol mixers, the V-1 will do black luma key, and the V-4 will do both types of luma key and chroma key. Both will also do a selection of other effects.

 

PN

[gnomatron]

I have one of the MX10s that Paulears mentions - it was 50 quid from ebay, useful bit of kit, worth getting a hold of one if you can get it at that price.

 

The V4 or MX50 are probably much better options, or you could do it in software; Arkaos VJ does it pretty well, as would most other Vj software, I imagine, i.e. resolume, vjamm, etc.