Dissolve Node

The Dissolve node performs a cross-dissolve from the A image (top input) to the B image (bottom input). The dissolve is calculated by multiplying the A image by the dissolve value (V), and adding the result to the B image multiplied by (one minus the dissolve value):

R = [A * V] + [B * (1 - V)]

Dissolve Parameter Tab

Dissolve

In the Dissolve parameter, the value you specify controls the transparency of the A image: a value of 0 represents a complete dissolve to the B image, a value of 0.5 is a 50% dissolve, and a value of 1 represents no dissolve from the A image.

Animating the Dissolve Value

You can use the STED functionality associated with the Dissolve parameter to control the rate of dissolve over time, or to change the flow of the cross-dissolve such that the B image dissolves into the A image. In the STED, a single function segment in the graph represents the entire dissolve operation by showing the A image transparency throughout the frame range.

To cross-dissolve evenly from image A to image B, for example, at the first frame the A image is at maximum value (opaque). You would typically use a linear function to bring the A image evenly from maximum value at frame 1 to the minimum value at the final frame. Of course, different functions can be applied to create pulsating or other effects.

On the other hand, if the A image is set at 0.5 transparency uniformly across the graph, the result would be a composite image where both inputs were 50% transparent throughout the range of frames.

Note:
A complete description of the Chalice "Space-Time Editor (STED) " is available in chapter 9 .



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