1. A computer-implemented method for removing false-positive foreground pixels from a video frame, comprising: extracting, via one or more processors, a foreground image from the video frame using a background model image; determining, based on at least the foreground image and portions of the background model image used as a proxy for an illuminance component of the foreground image, an approximated reflectance component of the foreground image, wherein the portions of the background image are pixels that correspond to respective pixels in the foreground image and wherein the approximated reflectance component provides approximated reflectance values for the respective pixels in the foreground image; and removing from the foreground image pixels having approximated reflectance values less than a first threshold value.