Digital Image Compression
نویسندگان
چکیده
When several gray midtones are present, like a black and white photo, two values are no longer sufficient to encode all the possible gray intensities, and to each pixel must be associated a numerical value, proportional to the brightness of that point. Typical choices for these values fall in the ranges 0 31 or 0 255 (requiring respectively 4 and 8 bits for each pixel). This second kind of image is referred to as a gray-level picture.
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