Abstract: When image data of a target container obtained by an image pickup unit such as a CCD installed on a hoisting accessory is processed, and a line approximating the arrangement of a pixel group which causes a change in luminance or hue larger than a set value can be fitted thereto, the pixel group having the arrangement that can be approximated by such a line is determined as a ridge of the container, that is, one representing the edge of the container held by the hoisting accessory, to detect the position of the target container. Thereby, edge extraction of the target container by the processing of the image data obtained by the image pickup unit such as a CCD camera installed on the hoisting accessory can be reliably and positively performed, while eliminating influences of various situations and conditions in the actual operating environment, and relative position detection of the target container and the suspended container can be performed accurately and reliably, by utilizing the edge extraction.

Abstract: When image data of a target container obtained by an image pickup unit such as a CCD installed on a hoisting accessory is processed, and a line approximating the arrangement of a pixel group which causes a change in luminance or hue larger than a set value can be fitted thereto, the pixel group having the arrangement that can be approximated by such a line is determined as a ridge of the container, that is, one representing the edge of the container held by the hoisting accessory, to detect the position of the target container. Thereby, edge extraction of the target container by the processing of the image data obtained by the image pickup unit such as a CCD camera installed on the hoisting accessory can be reliably and positively performed, while eliminating influences of various situations and conditions in the actual operating environment, and relative position detection of the target container and the suspended container can be performed accurately and reliably, by utilizing the edge extraction.