How many levels of brightness are available in an 8-bit grayscale image?

An 8-bit grayscale image can represent a range of brightness levels because each pixel in the image is assigned an 8-bit value. In digital imaging, with 8 bits allocated to each pixel, you can represent (2^8) different values. This is calculated as follows:

• Each bit can have 2 states: 0 or 1.
• Therefore, with 8 bits: (2^8 = 256).

This means that the 8-bit grayscale image can encode 256 distinct levels of brightness, ranging from 0 (black) to 255 (white), with various shades of gray in between. Each value corresponds to a different degree of brightness, providing detailed representation in the grayscale spectrum.

Other potential values like 128, 64, and 512 don’t derive from the calculation of (2^8) and therefore do not accurately reflect the number of levels of brightness in an 8-bit image.