A adaptive thresholding algotithm for motion detection based on two-dimensional spatio-temporal fuzzy entropy principle is proposed.A fast solution for calculating the two-dimensional fuzzy entropy threshold is deduced

in which repeated calculation is avoided by using integral and iterative operation

and the various calculation operation is reduced from

O(N

4

)

to less than

O(N

3

)

for

N

gray-level image.The motion detection is reduced to two binary partition problems

and two-dimensional spatio-temporal fuzzy entropy principle is used to determine the threshold

T

where the explicit function form or parameters of background distribution are not needed to be known.The experimental results show that the information of m

oving objects which have low contrast to background can also be extracted completely by this method in real time.