An image processing apparatus includes a hardware processor configured to function as: a first generation unit that, from a first frame image and a second frame image in a past frame immediately successive to the first frame image, generates a first motion map showing a presence region of a moving object; a second generation unit that generates a moving object passage map showing a moving object passage region, by subtracting the first motion map from a past map image showing a presence region of the moving object included in a past frame image; a third generation unit that generates a second motion map by integrating the first motion map and the moving object passage map multiplied by a first value; and an adjustment unit that, based on the second motion map, adjusts a parameter related to noise reduction processing of the first frame image and the second frame image.