The color range typically goes from 0 to 255 because it conveniently maps to an 8-bit byte, which is a fundamental unit of data in computing.
Here's a breakdown:
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Binary Representation: Computers store data in binary (0s and 1s). An 8-bit byte can represent 28 = 256 distinct values.
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Starting from Zero: Counting starts from zero, so the range is 0 to 255 (inclusive) to utilize all 256 possible values.
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Ease of Storage and Processing: Using a byte for each color component (red, green, blue) is efficient for storage and processing. Each color channel can then be easily represented by a single byte, allowing for a total of 256 shades of each color.
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RGB Color Model: In the RGB color model, each color is represented by a combination of red, green, and blue components. Each component is assigned a value from 0 to 255. Therefore (256 256 256) is equal to over 16.7 million different colors.
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Historical Context: This convention became established early in computing history, when memory and storage were much more limited. Using 8 bits per color component offered a good balance between color depth and resource usage.
In summary, the 0-255 range for color representation is primarily due to the efficient use of 8-bit bytes in computer systems, providing a practical balance between color resolution and data storage. While higher bit depths offer more colors, 8 bits per channel remain common and well-supported.
