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Noise effect, Noise alpha effect – Adobe Premiere Pro CS4 User Manual

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USING ADOBE PREMIERE PRO CS4

Effects and transitions

Last updated 11/6/2011

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

Noise effect

The Noise effect randomly changes pixel values throughout the image.

Amount Of Noise

The amount of noise to add.

Noise Type

Use Color Noise to add random values to the red, green, and blue channels individually. Otherwise, the

same random value is added to all channels for each pixel.

Clipping

Clips color channel values. Deselecting this option causes more apparent noise.

Noise Alpha effect

The Noise Alpha effect adds noise to the alpha channel.

Noise

The type of noise. 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 high-
contrast noise.

Amount

The magnitude of the noise.

Original Alpha

How to apply the noise to the alpha channel:

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%

transparent areas.

Edges

Produces noise only in partially transparent areas, such as the edge of the alpha channel.

Overflow

How the effect remaps values that fall outside the grayscale range of 0-255:

Clip

Values above 255 are mapped to 255. Values below 0 are mapped to 0.

Wrap Back

Values above 255 or below 0 are reflected back into the 0-255 range. For example, a value of 258 (255+3)

is reflected to 252 (255-3), and a value of -3 is reflected to 3.

Wrap

Values above 255 and below 0 are wrapped back around into the 0-255 range. For example, a value of 258

wraps around to 2, a value of 256 wraps around to 0, and a value of -3 wraps around to 253.

Random Seed

An input value to the random number generator for the 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.

Noise Phase

Specifies the placement of noise. This control is active only if you choose Uniform Animation or Squared

Animation.