Autodesk 62205-051408-9001 User Guide - Page 631

Basic Keying Techniques ❚❘❘ if the blue screen contains artifacts. See Keying Uneven Blue Screens. Blur-Applies a blur filter to the key-in source. This is useful when the blue screen is grainy. Click the Key-In Blur button to enable the blur, then set the blur width and height. These values determine the number of adjacent pixels used to blur each pixel. A Gaussian blur is used by default, but you can change the type to a Box blur in the Filter Type list. Setups Use these controls to import and export setups from Autodesk SGI-based products, as well as setups created in other Combustion workspaces. Import-Imports Keyer setups. Click Import, navigate to the location of a saved setup file, select the file, and then click Open. The imported setup is applied to the current Keyer. Export-Exports Keyer setups. Click Export, navigate to the location where you want to save the setup file, enter a file name, and then click Save. The current Keyer setup is saved. Colors Use these controls to customize the Comp background and the Plot bar colors. Comp-Determines the color of the solid background used when the output is set to Comp. To change the color, click the color box and select a color using the Pick Color dialog that appears. For more information on the Comp Output, see Output Options. Plot Bar-Determines the color of the bar that appears when you plot a color in the Key, Curves, or Color controls. Miscellaneous The following controls are also available. Composite Operation-Use Punch Back with computer graphics (CG) images in which the area to be keyed out is pure black. Use Blend if the color to be keyed out is not pure black (most digitized footage). Filter Type-Determines the type of blur used when you apply a matte blur (in the Matte controls) or a key-in blur. It also affects the Shrink and Erode operations: • A Box blur blends each pixel with adjacent pixels in the X and Y directions. • A Gaussian blur performs sub-pixel blending based on all surrounding pixels. It creates a smoother effect but is more processing intensive. Guess Key Color-Enable this option for Combustion to guess the key color when you first apply the Keyer operator. Output Matte As Use this control to determine how the output of the Keyer is used in the composite. Key-Outputs the matte as a key; in other words, the matte determines which parts of the keyed image are transparent. Selection-Ouputs the matte as a selection. When you choose Selection, the Invert option appears. Basic Keying Techniques There are as many keying techniques as there are compositers, and it takes some practice to find the best approach for any given footage. The amount of finessing required depends on where the key will fit into the overall composite as well as the format of the final output. This section gives an overview of one of these techniques. You will find detailed procedures in subsequent sections. 615