A video compression apparatus for compressing video data as a series of frames outputted from an imaging element that has a plurality of imaging regions for imaging a subject and for which imaging conditions can be set for the respective imaging regions, includes: a setting unit configured to set, based on a plurality of imaging conditions, a search region within a reference frame used for a processing to detect, based on a compression target region, a specific region in the reference frame; and a generation unit configured to generate, based on the processing using the search region set by the setting unit, the specific region to thereby generate a motion vector.