What is temporal neighborhood? I read in a paper http://tcts.fpms.ac.be/publications/regpapers/2011/nrmmbgtd_icvs_LNCS.pdf about spatio-temporal filters, which is applied to frames of the videos. I could not understand these terms in the paper if anyone can help.

3D Low Pass Filtering

Temporal Neighborhood

Spatio Temporal Filters
The temporal neighborhood refers to data nearby in time. That is; data located in the frames just before and just after the current frame.

The spatial neighborhood on the other side refers to the data nearby in space. In this case this is the pixels nearby in the same frame.

Spatio-temporal filters (which is 3D filters) takes both nearby pixels in the current frame and nearby pixels in nearby frames into account. In this way you can take advantage of information from more than one frame, which is often a good idea since most video sequences does not change much from frame to frame.