Blender GreenScreen Keying Concepts [2011, ENG]

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Blender GreenScreen Keying Concepts

Год выпуска: 2011
Производитель: cmiVFX
Сайт производителя: http://www.cmivfx.com/
Автор: Sebastian Koenig & Chris Maynard
Продолжительность: 1:48:20
Тип раздаваемого материала: Видеоурок
Язык: Английский
Файлы примеров: присутствуют
Формат видео: MP4

Standard Keying Tools
There are various keying nodes available in Blender’s node-editor. Often people try to use the color- or chroma-key, which surely are useful in some situations. The best key however is the channel-key, which is able to create decent mattes with fine edges. In this video you will learn how to use the channel-key to get a solid alpha-channel instantly, but also how to enhance and preprocess your footage to improve your key and create a smooth edge with lots of detail.

Custom Keyer
When the standard keying-nodes are not enough, you can still build your own keyer to fit your needs. Separating an image into different channels gives you a lot of control over each color and with some pixel math and rewiring you can come up with your own self made keys that sometimes work better and give more detail than the off-the-shelf solutions. Combined with garbage-mattes and rotoscoping you can solve even difficult shots with motion-blur, reflections and unevenly lit green screen.

Enhancements
But even the best alpha-channel will not help if your image suffers from color spill and doesn’t integrate well into the background. This video will show you how to enhance DV-footage to improve your key, how to get rid of color-spill and how to apply techniques like light wraps to really integrate your keyed footage into the background.

Compositing
Once your key is ready you’ll probably want to save your keyed footage and use it in another composite. In the last chapter you will learn how to do that and how to apply some little post-processing tricks.

Note:
This tutorial is has been recorded with a development version of Blender 2.56a. There are still a few exciting months ahead until the final, stable version will be released. Bugs will be fixed, some little features might be added. But don’t worry! The techniques in this tutorial don’t rely on fancy tools, so you can use them with almost any version of Blender. But for reference we have included a current development version of the software.

About the author:
Sebastian König is a German 3D-artist and is working as a freelancer and CG-instructor. He has been working for various studios and companies, creating animations, stills, visualizations and commercials as well as feature film VFX. As a Blender Foundation Certified Trainer he has been teaching Blender at international courses, universities, schools and companies and enjoys sharing his experience and knowledge with the Blender community.
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