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Use Levels to adjust the gamma to change the brightness values of the middle range of
gray tones without dramatically altering the shadows and highlights.
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A. Channel B. Histogram C. Input Black D. Output Black E. Gamma F. Output White G. Input
White
For more information, see the After Effects product section on Adobe's Web site.
Posterize
Use this effect to specify the number of tonal levels (or brightness values) for each channel
in an image. Posterize then maps pixels to the closest matching level. For example,
choosing two tonal levels in an RGB image gives you two tones for red, two tones for
green, and two tones for blue. Values range from 2 to 255. Although the results of this
effect are most evident when you reduce the number of gray levels in a grayscale image,
Posterize also produces interesting effects in color images.
Use Level to adjust the number of tonal levels for each channel to which Posterize will map
existing colors.
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A. Original image B. Posterize applied with five levels of color C. Threshold applied
Threshold
Use this effect to convert grayscale or color images to high-contrast, black-and-white
images. Specify a certain level as a threshold; all pixels lighter than the threshold are
converted to white and all pixels darker to black.
Audio effects
This category contains audio effects that add ambiance to a layer, enhance or correct
audio characteristics, and create effects. You can apply audio effects to existing audio
footage, or synthesize just about any sound by combining the Tone effect with other
audio effects.
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