Matte Controls

Use the Matte controls to refine the matte created by the keying process.

Shrink

Removes pixels from the edge of the matte. Enable Shrink and set the width—the amount to add or remove from the edge of the matte.

Erode

Adds transparency to the edge creating a smoother matte.

Blur

Applies a blur filter to the matte. Enable Blur and set the amount to blur in the vertical and horizontal directions. By default a proportional Gaussian blur is used. You can set the blur to Box blur in the Setup controls. See Setup Controls.

Lift

Adds an offset to the matte value of every pixel. Set the Lift to a negative value when you want to darken shadow areas in your matte.

Gain

Multiplies the matte value of every pixel by a percentage. Increase Gain to brighten the highlights.

Invert

Inverts the keyed matte. Transparent regions of the front layer become opaque, and vice versa.

Zoom

Zooms the histogram.

Histogram

Use the histogram to remap the brightness of the matte:

• Drag the input sliders inward to remove grays from the matte and increase contrast.
• Drag the output sliders inward to reduce contrast in the matte.