An image processing device is for generating a smoothed image with an input image blurred. The device includes first low pass filters each set with a different range of level value, using each pixel in the input image or a first input image generated based on the input image as a pixel of interest, extracting each pixel that has a level value of each pixel in a filter size within a range of level value, and generating a first level value limit smoothed image by smoothing a level value of an extracted pixel to be used as a level value of the pixel of interest. The device also includes a first synthesis processing unit that uses each pixel in the input image or a second input image generated based on the input image as a processing object pixel.