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Calculations effect, Compound arithmetic effect – Adobe Premiere Pro CS3 User Manual

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ADOBE PREMIERE PRO CS3

User Guide

306

Calculations effect

The Calculations effect combines the channels of one clip with the channels of another clip.

Original images (left and center), and with effect applied (right)

Input Channel

The channel to extract and use as input to the blending operation. RGBA displays all channels

normally. Gray converts all color channel values for a pixel to the luminance value of the original pixel. Red, Green,
or Blue converts all color channel values for a pixel to the value of the selected color channel for the original pixel.
Alpha converts all channels to the value of the alpha channel for the original pixel.

Invert Input

Inverts the clip before the effect extracts the specified channel information.

Second Layer

The video track with which Calculations blends the original clip.

Second Layer Channel

The channel to be blended with the input channels.

Second Layer Opacity

The opacity of the second video track. Set to 0% for the second video track to have no

influence on the output.

Invert Second Layer

Inverts the second video track before the effect extracts the specified channel information.

Stretch Second Layer To Fit

Stretches the second video track to the dimensions of the original clip before blending.

Deselect this option to center the second video track on the original clip.

Preserve Transparency

Ensures that the original layer’s alpha channel isn’t modified.

Compound Arithmetic effect

The Compound Arithmetic effect mathematically combines the clip to which it’s applied with a control layer. The
Compound Arithmetic effect is intended only to provide compatibility with projects created in earlier versions of
After Effects that use the Compound Arithmetic effect.

Second Source Layer

Specifies the video track to use with the current clip in the given operation.

Operator

Specifies the operation to perform between the two clips.

Operate On Channels

Specifies the channels to which the effect is applied.

Overflow Behavior

Specifies how pixel values that exceed the allowed range are treated:

Clip

Indicates that the values are limited to the allowed range.

Wrap

Indicates that values exceeding the allowed range wrap around from full on to full off, and vice versa.

Scale

Indicates that the maximum and minimum values are calculated and the results are stretched down from

that full range to the range of allowable values.

Stretch Second Source To Fit

Scales the second clip to match the size (width and height) of the current clip. If this

option is deselected, the second clip is placed at its source’s current size, aligned with the upper left corner of the
source clip.

Blend With Original

The effect’s transparency. The result of the effect is blended with the original image, with the

effect result composited on top. The higher you set this value, the less the effect affects the clip. For example, if you

April 1, 2008