2017

Table Of Contents
6 To manually select a patch type, select it from the Patch box.
NOTE If you want to reset the patch so that you can automatically select the patch type, you must disable
the patch and set the patch type to Off. You can then resample an area in the image and generate a patch
type.
7 To improve the patch, use the Patch controls.
To:Drag:
Increase or decrease the colour range that is included in the patch.Range
Soften the edge.Soft
NOTE To reset Patch parameters, click the Reset button, next to the sampling box.
Creating a Key by Extracting a Single Colour with the Channel
Keyer
You can extract one of the three primary colours (red, green, or blue), or a custom colour from the key-in
clip. This method is useful for clips containing transparencies such as glass or smoke.
Extracting a Primary Colour
Extract one of the three primary colours from the key-in clip when you have a front clip shot in front of a
blue, red, or green screen.
To create a key by extracting a primary colour:
1 From the Start Mode dropdown list, select Reset to Channel and click Confirm.
The Channel keyer processing pipeline is displayed in the schematic view.
2 Double-click the Channel Keyer node.
The Channel controls appear.
(a) Channel Mode box (b) Softness field
3 Select one of the primary colour options (Red, Green, Blue) from the Channel Mode box.
4 Enable More to enhance the keying effect.
The More option extends the range of the colour to be extracted from the key-in clip.
5 Increase or decrease the softness for the key using the Softness field.
The softness value determines how much of the key-in clip is partially transparent in the matte. Softness
creates a smoother transition between the front and back clips in the composite clip.
6 Click Result to see the result of your key.
696 | Chapter 16 Chroma Keying and Working with Green Screens