Abstract
In an image processing method, an image obtained by capturing an image of a workpiece placed on a loading surface from a predetermined height with a two-dimensional camera is processed to recognize a position of the workpiece as a coordinate value in units of pixels, and the coordinate value in units of pixels is converted into a coordinate value in units of lengths using a resolution serving as an amount of change in length per unit pixel of the image. In the method, a first relationship that is a relationship between a unit resolution serving as an amount of change in resolution per unit height and a working distance serving as a distance between a target object and a lens of the two-dimensional camera is acquired. Next, a resolution of the image of the two-dimensional camera with respect to the loading surface of the workpiece at an installation height of the two-dimensional camera is measured when the two-dimensional camera is installed to estimate a working distance for measurement, and the unit resolution is estimated based on the estimated working distance and the first relationship. A height of the workpiece is acquired, and the resolution of the image is corrected based on the acquired height of the workpiece and the estimated unit resolution.