Studying the research paper Multidirectional Scratch Detection and Restoration in Digitized Old Images, E. Ardizzone et al., 2011:
I have several questions regarding this section (5. Restoration),
- How can I obtain the average gradient on an area in an image?
- How can I obtain a vector that minimizes the sum of absolute differences (SAD) in an image?
- Which block-matching approach is being suggested here?
- Which factor determines the distance of the blocks from the scratch line?
I could understand the equation (6), but I could not understand how I can implement it practically like in MATLAB or in any programming language.