Mathematics - Mean & Median Background subtraction

In Mean Background subtraction or mean filter background subtraction the background is the mean of the previous n frames

( Σ i=0 to n-1 (It- i(x,y)) )/ n

In Median background subtraction the background is the median of the previous n frames

median{ I t-i (x,y) }


i ∈ { 0,1,2,3, ... n-1 }


The mathematics that i used in approximate median background subtraction was:

if It (x,y) > B t(x,y) ⇒ B t(x,y) + 1

if It (x,y) < B t(x,y) ⇒ B t(x,y) - 1



This method will eventually converge where half of the pixels are greater than the background and another half less than the background.

Results can be found here:
Result