Rolling median algorithm in C

Question

I am currently working on an algorithm to implement a rolling median filter (analogous to a rolling mean filter) in C. From my search of the literature, there appear to be t

Answer 1

If you just require a smoothed average a quick/easy way is to multiply the latest value by x and the average value by (1-x) then add them. This then becomes the new average.

edit: Not what the user asked for and not as statistically valid but good enough for a lot of uses.
I'll leave it in here (in spite of the downvotes) for search!