ADOBE PREMIERE PRO 2.0
User Guide
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Drag the Threshold slider left to 0 to turn off the value, so that all pixels in the selection or image can be examined.
(The threshold determines how different the pixels’ values should be before they are eliminated.)
Note:
The Threshold slider gives greater control for values between 0 and 128—the most common range for images—
than for values between 128 and 255.
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Increase the threshold gradually by entering a value or by dragging the slider to the highest value possible that
eliminates defects.
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Select the Operate on Alpha Channel checkbox to apply the filter to the alpha channel.
Noise Alpha effect
The Noise Alpha effect adds uniform or squared noise to the alpha channel of a source clip.
Noise Alpha effect: Original video track image (left), Original Alpha set to Clamp (center), and Noise Alpha combined with Direction Blur
(right).
Adjust the following controls for the Noise Alpha effect:
Noise
Specifies the type of noise the effect uses. Unique Random creates equal amounts of black and white noise.
Squared Random creates high-contrast noise. Uniform Animation creates animated noise, and Squared Animation
creates animated contrast.
Amount
Specifies the amount of noise that’s added to the clip.
Original Alpha
Specifies how to apply noise to the alpha channel of a clip:
•
Add
Produces equal amounts of noise in the transparent and opaque areas of the clip.
•
Clamp
Produces noise in the opaque areas only.
•
Scale
Increases the amount of noise proportionate to the level of opacity and produces no noise in 100% trans-
parent areas.
•
Edges
Produces noise only in partially transparent areas, such as the edge of the alpha channel.
Overflow
Specifies how the effect remaps values that fall outside the grayscale range of 0-255.
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Clip
Displays values above 255 as opaque and values below 0 as transparent.
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Wrap Back
Forces values back into the 0-255 range, creating subtle details. For example, a value of 256 wraps back
to 254, and a value of -1 wraps back to 1.
•
Wrap
Forces values back into the 0-255 range by starting values above 255 at low color values and starting values
below 0 at high color values. For example, a value of 256 is wrapped to 0, 257 is wrapped to 1, and 258 is wrapped to
2. Conversely, a value of -1 is wrapped to 255, -2 is wrapped to 254, and -3 is wrapped to 253.
Random Seed
Specifies a random value for noise. This control is active only if you choose Uniform Random or
Squared Random.
To produce flashing noise, animate the Random Seed control. To create smoothly animated noise, animate the Noise
Phase value.