An image processing apparatus includes display means for displaying a zoom image resulting from enlargement of a certain area in an original image to a zoom area; important object determining means for determining whether the absolute value of the difference in pixel value between a pixel on a boundary line, which is the outermost circumference of the zoom area, and the pixel that adjoins the pixel on the boundary line in the direction perpendicular to the boundary line and outward from the zoom area is lower than or equal to a predetermined threshold value to determine whether any important object is across the boundary line; and resetting means for resetting a zoom parameter used for determining the zoom area if the important object determining means determines that any important object is across the boundary line.