Lookup tables
Lookup tables can be used for fast computation of homogeneous point operations. Determine the equations for the computation of lookup tables for the following point operations. The images have Q = 2P discrete values. Also answer the question whether the point operation can be inverted.
1. Negative image (white becomes black and vice versa)
2. A lookup table that indicates the underflow and overflow of gray values. Underflow should be marked in blue, overflow in red. Hint: color output requires three lookup tables, one each for red, green, and blue (additive color mixing).
3. Contrast enhancement: a small range of S gray values should be mapped to the full gray value range of 2P gray values.