I was thinking about 2D filtering. But your comment triggered a new DuckDuckGo search and it happened to have some bits of information :-) https://www.extron.c

I was thinking about 2D filtering. But your comment triggered a new DuckDuckGo search and it happened to have some bits of information :-) https://www.extron.com/article/ntscdb4 https://www.extron.com/article/ntscdb4