1. An image processing apparatus comprising: a camera interface section configured to be connected to an imaging section, the imaging section taking an image of an object to be measured to produce image data, the image data produced by the imaging section being inputted to the camera interface section; a plurality of arithmetic processing sections configured to process the image data; a display screen output section configured to be connected to a display section to output display image data to be displayed on the display section; an input section configured to accept input from an outside; a storage section configured to store a plurality of processing units configured to process the image data; a processing registration section configured to register a processing procedure, the processing procedure comprising a combination of the processing units selected by the input from the input section and forming a flow; a mode selection section configured to selectably display a plurality of parallel processing modes configured to respectively indicate different kinds of parallel processing on the display section and to accept the selection of the parallel processing mode from the input section; and a parallelization section configured to allocate each of a plurality of processing units configured to process image data and included in a target processing procedure to one of the plurality of arithmetic processing sections according to the parallel processing mode selected by the mode selection section; wherein corresponding arithmetic processing sections are configured to process corresponding processing units of the target processing procedure in parallelized flows, and the processing registration section is further configured to output the display data of the processing units included in the processing procedure according to a performance sequence determined by the input from the input section.