1. An image processing apparatus, comprising: a distance information generation portion configured to: generate a first distance information about an object to be measured, wherein the first distance information is generated based on a phase difference between images provided by a plurality of first cameras having a first base length, and generate a second distance information about the object to be measured, wherein the second distance information is generated 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; a distance extraction portion configured to extract a distance between an imaging position and the object to be measured based on the first distance information and the second distance information, wherein the extracted distance is utilized to process at least one image; and a refocus coefficient setting portion configured to calculate a refocus coefficient based on a depth of a designated captured image of an image sensor, wherein the designated captured image corresponds to a refocus surface of the object to be measured, wherein the designated captured image is captured by the image sensor based on the refocus coefficient.