[KAK] - How does KAK work?

[SecondMan]

KAK is a keyer that started off as an exercise to mimic Nuke's IBK functionality in a relatively simple Fusion macro. Since that was accomplished back in version 1, now almost two years ago, it has grown far beyond that, and it is currently one of the most advanced keyers around, holding its own amongst the likes of Primatte, Ultimatte and Keylight.

It is also worth noting that the dozens of different techniques used within KAK are the result of over a decade of hands-on keying experience, and have been used very successfully on many projects. However, it is the first time that all of these techniques have been compiled and meticulously finetuned to work together in a single tool.

Even though it has been continuously adapted to make working with it as easy as possible, some have found the number of features a little daunting at first sight. However, once you know what process is going on under the hood - and hence, what it is you can expect to happen - it turns out KAK is arguably one of the easiest, best, and fastest keyers to use.

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So how does KAK actually work? This brief introduction describes what goes on inside KAK, from the moment you pick you first Screen Color to pulling your first key, without going into the nitty gritty of every single parameter. This is about understanding the process first and foremost, which will help you get started in no time at all!

KAK_Intro_fig_1.jpg

This is a typical example of a subject shot in front of a green screen. What KAK needs to do is create a Clean Plate by removing the subject and filling in that empty space with more green. Once you tell KAK what is certainly green screen, and what certainly is NOT green screen, it can then separate the subject from the green screen, while retaining as much of the subject's detail as possible.

KAK_Intro_fig_2.jpg

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The pink/purple areas in these images is what is telling KAK what is certainly green screen. It's very important that this area does not contain any of the pixels belonging to the subject. This is more important than trying to cover as much of the green area as possible:

KAK_Intro_fig_3.jpg

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KAK will then cut out the non-green pixels, and fill in the resulting void with appropriate values of green. This results in exactly the kind of Clean Plate required for the creation of a good matte.

KAK_Intro_fig_6.jpg

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All that's left to get started properly is to let KAK do its magic:

KAK_Intro_fig_8.jpg

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This process has just described the first steps of every single good looking key you will ever pull in KAK. Really, this is it! Just set your output to Kick Ass Key and you're good to go.

From here, I suggest just walking through the many parameters under the different tabs and look at your RGBA channels and different Outputs to see what happens when you change them. In the meantime, more in-depth tutorials will be on their way…

Image: Courtesy Blender Foundation, Creative Commons Blender Foundation | mango.blender.org

[Whelkn]

Thanks alot

[SecondMan]

You're welcome!

(And before anyone asks - yes, video tutorials are also on the cards.)

[French_Fry]

great! looking forward to trying out KAK3!

[Miltos]

Finally some guide on how this thing works! Great post!

[Dunn]

Finally some guide on how this thing works! Great post!

+1 Oh Yes! I gave up on the last version .. was just pressing buttons and moving sliders.. hoping it would make something cool!

[robocop]

Thank you SecondMan!
Thanx God I don't have blue\green screen's materials in our full-cg animation projects..
But, it so cute when artists share their stuff with other artists.. P2P (peoples to peoples) philosophy is always amazing thing!
heck! with such a great tool - I should ask our rendering sup to render our images just on green screen ! why we need alpha channel any more?!??!

[ernesttx]

Had a quick play with this yesterday and it was great. A video tutorial would be most excellent for explanation of some of the buttons and drop downs. But overall, great tool.

[SecondMan]

Thank you SecondMan!
Thanx God I don't have blue\green screen's materials in our full-cg animation projects..
But, it so cute when artists share their stuff with other artists.. P2P (peoples to peoples) philosophy is always amazing thing!
heck! with such a great tool - I should ask our rendering sup to render our images just on green screen ! why we need alpha channel any more?!??!

Haha, you'd be laughing but I've actually known a guy who did that. He had no idea he could render an alpha channel.

Mind you, this was in the dark ages.

[SecondMan]

Had a quick play with this yesterday and it was great. A video tutorial would be most excellent for explanation of some of the buttons and drop downs. But overall, great tool.

Thanks ernesttx!

Video tutorials will come. Now that I am pleased with the interface it makes sense to do them. And it's true that there is a lot going on under the hood...

[mdharrington]

thanks for this...much appreciated.

a couple of questions...what comprises the keying part after clean plate generation. Does your tool contain the fusion ultra keyer, or is it something completely custom.

Also when doing your tutorial, it wouldvery cool and informative to break down the traditional techniques that went behind the creation of this tool. A lot of us will not have your high end production expertise and would not know be aware of the tricks that KAK encapsulates.

Thanks again

[SecondMan]

thanks for this...much appreciated.

a couple of questions...what comprises the keying part after clean plate generation. Does your tool contain the fusion ultra keyer, or is it something completely custom.

It's completely custom. The Ultrakeyer was a part of KAK 1 and 2, but no longer needed in 3. It was never used for the main keying part though, that was always custom - it was used for the clean plate generation.

Also when doing your tutorial, it wouldvery cool and informative to break down the traditional techniques that went behind the creation of this tool. A lot of us will not have your high end production expertise and would not know be aware of the tricks that KAK encapsulates.

Of course, understanding the process is key (hah!). Also don't forget the tool is completely open, so you can just open it up and see how it's done if you want to get into per-node nitty gritty. The layout is pretty clear and most nodes have names relevant to their function.

[Toaster]

Great tool. Getting amazing results with hair! Thank you.

[SecondMan]

Great tool. Getting amazing results with hair! Thank you.

Thanks Toaster! Nice to hear!

[SecondMan]

So... in the spirit of the current Fusion Holiday Season, this finally happened:







Hope you like it. Making video tutorials is bloody hard. My hat goes off to people who find this easy.

Enjoy!