Data Discovery for Learners of All Ages
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What is a Digital Image?A digital image is:
Pixels also correspond to distances and areas. For example, a length of twenty pixels in an image may represent one micron in an electron micrograph or one hundred kilometers in a satellite image. The more pixels there are in an image, the greater its resolution; an image with a high number of pixels and a high bit depth therefore more closely represents the actual thing that was measured. Bit depth tells you how much data is being used to define each pixel in an image. A bit is the smallest unit of data, and comes in two possible states: either 1 or 0 (or on/off, or black/white). A black-and-white image is a 1-bit image, since only one bit is needed to define each pixel; 8-bit and higher images give you a lot more information. Unlike graphics, where meaning comes only from the patterns formed by many pixels, each pixel in a digital image may contain meaningful information.