Exercises of Chapter 3 in Textbook: No.2 - Suppose we decide to quantize an 8-bit grayscale image down to just 2 bits of accuracy. What is the simplest way to do so? What ranges of byte values in the original image are mapped to what quantized values? Answer: Just use the first 2 bits in the grayscale value. I.e., any values in the ranges 0000 0000 to 0011 1111, 0100 0000 to 0111 1111, 1000 0000 to 1011 1111, 1100 0000 to 1111 1111 are mapped into 4 representative grayscale values: 00, 01, 10, 11. In decimal, these ranges are: 0 to (2 6 -1), 2 6 to (2 7 -1), 2 7 to 2 7 + (2 6 -1), 2 7 + 2 6 to (2 8 -1). i.e., 0 to 63, 64 to 127, 128 to 191, 192 to 255. Then reconstruction values should be taken as the middle of these ranges; i.e., 32, 96, 160, 224.