Glossary

A

adjustment layer

A special kind of layer you can add to an image that enables you to adjust the levels, brightness/contrast, hue/saturation, gradient, invert, threshold, or posterize commands without altering the image layers located below the adjustment layer in the Layers palette.

alpha channel

An alpha channel represents the fourth channel that composes a 32-bit graphic image. It contains 256 shades of pixel data reserved for storing transparency data, but it is also responsible for defining how the pixels in each eight-bit red, green, and blue channel are overlapped with each other to create the resulting full-color image.

Analog-to-Digital Converter (ADC)

A device containing one or more chips that converts analog data into digital data. ...

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