1. A computer-implemented method for long-term understanding of background modeling, the method comprising executing on a processor the steps of: determining dimensional gradient model values for pixel image data extracted from features of input video data; defining average image pixel gradient model values for each pixel of the extracted pixel image data by averaging the determined dimensional gradient model values with the determined dimensional gradient model values of neighboring pixels as a function of their distance to the pixel; and estimating a background static image scene of the input video data to comprise pixels of the extracted pixel image data that are not background pixel model pixels, and that have average image pixel gradient model values that are not less than a threshold distance value from the average image pixel gradient model values of the background model pixels, or that have average image pixel gradient model values that are less than the threshold distance value from the average image pixel gradient model values of the background model pixels but are closer to the average image pixel gradient model values of another foreground model set of the pixels.