Abstract: The Identification of pointer meters’results on the basis of image processing is critical for pointer meters’ automatic checkup.For the angle method owns the shortcoming of imprecise result identification the image is proecessed after the pretreatment of the meters outfit image.Binary image extracted the useful imformation,with improved Hildtch thin to process binary image.Then,least square method is used to approximate meter head scales and pointer.On this basis,the method to combinate scale value considered as basis value with distance approach is proposed.The experiment concerned testifies the feasibility of the approach and shows that it has applied significance in the auto-examination of pointer meters.

Key words: thinned method； least square method； distance approach；