1. An image signal processing apparatus, comprising: a low pass filter part that performs a spatial low pass filter processing on a first image signal that is an input image; an image processing part for high resolution that generates a second image signal by performing an image processing for high resolution on an image after the low pass filter processing; and a comparison/selection part that compares corresponding regions in the first image signal and the second image signal, and selects either of the first image signal and the second image signal with respect to the regions based on this comparison result.