Abstract: Change detection apparatus for detection of changes between first and second stereoscopic image pairs obtained at different times of a substantially similar view, comprises: a two-dimensional image filter for comparing first and second image pairs to obtain an initial list of change candidates from two-dimensional information in the image pairs, and a three-dimensional image filter for comparing the image pairs at locations of the change candidates using three-dimensional image information. The apparatus retains those change candidates correlating with three-dimensional image change and rejects change candidates not correlating with three-dimensional image change, and produces a refined list of change candidates.