1. An image processing apparatus comprising: a distance information generation portion configured to generate first distance information about an object to be measured based on a phase difference between images provided by a plurality of first cameras having a first base length, and generate second distance information about the object to be measured based on a phase difference between images provided by a plurality of second cameras having a second base length that is different from the first base length; and a distance extraction portion configured to extract distance information from an imaging position and the object to be measured based on the first distance information and the second distance information.