Ultimatte AE ( AdvantEdge ) Node

Ultimatte AdvantEdge is a composite node optimized for foreground imagery processed with the Ultimatte PFG node (see chapter 16, "Matte Nodes " for complete descriptions of the other Ultimatte nodes).

Ultimatte AE enables you to correct edge artifacts and matte lines created by a number of factors including lighting problems, unwanted shadows, and detail generator enhancement settings often used on video and telecine equipment.

The AdvantEdge node works by identifying darker areas of the edges of a foreground matte that may represent undesirable edge artifacts. Because you may wish to preserve some of these darker areas while suppressing others, the node offers a wide range of controls to vary the strength, position, and direction of the filtering process that corrects edges of the matte.

The AdvantEdge node replaces the compositing step performed by the Mcomp node in the Basic Ultimatte Network illustrated in Overview of the Ultimatte Process in chapter 16. The node requires two inputs, a foreground image and a background image. The foreground image must contain an alpha channel.

Note:
Unlike the Mcomp node, Ultimatte AdvantEdge assumes that the premultiplication style of the foreground input is Ultimatte. For more information, refer to About Premultiplication at the beginning of this chapter.

AdvantEdge Parameter Tab

The AdvantEdge parameters allow you to specify how the edges of the foreground image will be adjusted in the composite. You can also access a work monitor to view the areas AdvantEdge has identified for correction.

Work Monitor / At Resolution

First, select a display resolution for the work monitor from the At Resolution popup menu. Then click the plus icon to display the work monitor for this node, which shows the composite image with a custom overlay superimposed on it. This overlay visually highlights transition areas of the matte (matte edges) identified by the node.

Work Monitor Display Parameters

The work monitor provides parameters to control the appearance of the overlay display. These do not affect the output; however, they enable you to control the color and transparency of the overlay, and whether the overlay covers edge or non-edge areas:

  • The Invert button determines whether the overlay will cover edges or non-edges. By default, the overlay display will cover all areas not identified as edges, displaying edge areas as they currently appear in the composite.
  • The Transparency tuner controls the overlay, in a range of 0 (transparent) to 100 (opaque). To see how the composite looks without the overlay, set this value to 0.
  • The Overlay Red, Green, and Blue parameters set the color of the overlay. By default, the overlay display is translucent red.
  • Operation

    The Operation parameter specifies the type of correction to perform:

    • Horizontal AdvantEdge specifies that the correction and smoothing operations search horizontally only; that is, that only the left or right inside edges be searched for edge-correction criteria. This means that Horizontal AdvantEdge will correct edges that run vertically in the image.
    • Vertical AdvantEdge specifies that the correction and smoothing operations search vertically only; which means that the upper or lower inside edges are searched. Vertical AdvantEdge will correct edges that run horizontally.
    • Full AdvantEdge applies both Horizontal and Vertical operations.
    • No AdvantEdge is useful if you would like to see how your composite would look without applying any edge correction.

    Position

    The Position parameter adjusts the center of the edge identified for correction by moving the edge away from or toward the outside of subject areas. This may help cover problem areas without increasing the overall thickness of the edge correction area.

    Width

    The Width parameter sets the width, or thickness, of edge correction. Increasing Width control too far may cause detail loss in the edge area.

    Correction

    The Correction parameter sets the strength, or amount, of gray/black suppression in the matte edges. Adjust this control until problem edges disappear. Advancing Correction too far may cause detail loss within the edge area.

    Smoothing

    The Smoothing parameter smooths hard or jagged object edges in the direction specified in the Operation menu. Smoothing is not often recommended, as it can degrade fine detail.

    Interlace (Video) Mode

    This parameter, when checked, configures AdvantEdge for video-type frames that have been split into frames of even or odd field lines. Because the AdvantEdge filtering works over several field lines, you must specify interlaced input for images that contain the single-line gaps.




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