1. A video signal processing apparatus for an endoscope, the video signal processing apparatus including an attachable/detachable endoscope including an image pickup section for picking up an image of a subject, and including a signal processing circuit capable of generating a video signal, the video signal processing apparatus comprising: a data reading section that reads parameter data unique to the endoscope from a memory provided in the endoscope, the parameter data being used in a process of generating the video signal performed by the signal processing circuit; an error determination section that determines whether or not the parameter data read by the data reading section has an error; an error data determination section that, if a result of determination by the error determination section indicates that the parameter data has an error, determines a type of the parameter data having the error; a control section that controls the signal processing circuit according to a determination result by the error data determination section, and a test data generation section that generates test data for each type of parameter data, based on the parameter data from the memory provided in the endoscope, wherein the data reading section reads the parameter data from the memory provided in the endoscope and reads the test data generated for each type of parameter data in the endoscope based on the parameter data, and the error data determination section determines the type of the parameter data which has the error by comparing the parameter data read from the memory and the test data generated by the test data generation section, for each type of the parameter data.