A vehicle surroundings monitoring apparatus inputs images taken by a stereoscopic camera, vehicle speeds, steering wheel rotation angles, yaw rates and ON-OFF signals of a turn signal switch. The modulator may be configured to generate a modulation signal in response to a data input signal. In the event a main column line and the associated regular columns are identified for replacement by a set of storage elements, the set additionally indicates whether the regular columns are regular columns in a single block of memory cells or multiple blocks.