An image processing device includes a processor including hardware, the processor implements an image acquisition process for acquiring a plurality of images including a first image and a second image； a filter process for extracting first to N-th frequency components using first to N-th bandpass filters； correlation calculation for obtaining first to N-th correlation calculation results at a target pixel by performing correlation calculation with an i-th frequency component in the first image and the i-th frequency component in the second image； a reliability calculation process for obtaining reliability of each of the correlation calculation results obtained； a weight setting process for setting a weight of each of the correlation calculation results using the reliability； and amount of disparity calculation for obtaining an amount of disparity using the weight and the first to the N-th correlation calculation results.
