5. A method according to claim 4, wherein the address words that define locations of the input scene having the first-mentioned selected spatial relationship with said predetermined location are modified by adding each of them to the first-mentioned offset word, and the address words that define locations of the input scene having the second selected spatial relationship with said predetermined location are modified by subtracting each of them from the second offset word.
8. A method according to claim 5, wherein the address words of the third sequence that define locations of the input scene having said selected spatial relationship with said predetermined location are modified by subtracting each of them from the offset word.