ANR Edge Color

Overview

A keyed or rotoed element often keeps the colour of the place it was shot in at its edges: a green or blue tint from the screen, or the warm or cool light of another location. Edge Color re-colours those edge pixels with the new background behind them, so the edge blends into the shot. The matte itself is never changed: nothing is eroded, blurred or choked.

Three sliders work separately. Color from Background gives the edge the background's hue and saturation but keeps its own brightness and texture. Luminance from Background moves the edge's broad brightness toward the background's. Detail from Background replaces the edge's fine texture with the background's, at the scale set by Detail Size.

The edge is the partly transparent part of the matte, chosen with Soft Edge Strength. For hard cutouts, Inward Reach and Inward Feather carry the treatment a set distance into the solid part of the element. Where ANR Light Wrap adds the background's light on top of the edge, Edge Color replaces the colour the edge already has; the two work well together.

Inputs

1. Foregroundrequired

   The keyed or rotoed element, premultiplied and placed where it sits over the background. Its alpha decides which pixels are edge.

2. Backgroundrequired

   The new background, aligned with the Foreground. The edge takes its colour, and optionally its brightness and texture, from here. Without it the Foreground passes through unchanged.

3. Maskoptional

   Limits the treatment: white allows it, black protects. Use it to keep an edge whose colour is already right.

Output. The treated Foreground, premultiplied, with its alpha unchanged, ready for your Merge. View can also show it over the Background (Composite), where it is treated (Edge Matte) or the smoothed background colour it uses (Background Sample).

Quick start

1. Add ANR Edge Color to the element after your key and despill, before its Merge over the background.
2. Connect the element to Foreground and the new background to Background. Leave View on Foreground and keep your Merge.
3. With the defaults the soft edge already takes the background's colour. Set View to Edge Matte to see which pixels are treated.
4. Raise Soft Edge Strength to reach the denser part of the edge. For a hard cutout, raise Inward Reach and Inward Feather to carry the colour into the solid part of the element.
5. If the edge is still too bright or too dark, raise Luminance from Background. If it still shows the old texture, such as a contaminated highlight, raise Detail from Background and set Detail Size to the size of that texture.
6. Balance the result with Color Saturation, Color Tint and Mix.

The panel

The node's panel as Nuke shows it, with the values of a new node. Click any control to see what it does; tabs and sections work as in Nuke.

All controls

Tips

• Hair and fine wisps: keep Inward Reach at 0 and work with Soft Edge Strength. Solid objects with a hard roto: raise Inward Reach and Inward Feather, and check the result in Edge Matte.
• Luminance from Background on its own keeps the edge's bright and dark texture, including a contaminated highlight. Add Detail from Background when that texture should go too.
• With the edge fully selected and all three sliders at 1, the edge matches the background completely and the element's own edge detail is gone. Keep them lower to keep some separation.
• Lower Color Sample Radius to follow small colour changes in the background; raise it for a calmer, averaged colour.
• Order in the comp: key, ANR Despill, Edge Color, ANR Light Wrap, then the Merge.

Good to know

• View: Composite already contains the Background. Don't merge it over the background again; use Foreground for your own Merge.
• The edge takes colour only where the Background has alpha. If some edges stay untouched, check that the Background's alpha is solid there.
• A black background has no colour, so the edge turns neutral there. A flat background has no texture, so Detail from Background smooths the edge's texture at Detail Size.
• Use the Foreground and Background in the same format, aligned, and in scene-linear colour.
• Runs on the CPU: no GPU and no AI model needed.

Works with

ANR DespillRemoves green or blue screen spill from a keyed element and brings back the brightness the spill took with it.ANR Light WrapWraps the background's light softly around the edges of a keyed or CG element, so it sits in the plate instead of looking cut out.ANR Edge Detail ExtensionRemoves the old background from the soft edges of a cut-out, hair and motion blur included, so it sits cleanly over a new background.