针对电表读数区域自动定位这一关键技术的具体应用,提出了一种适合四种类型机械式电表的读数区域自动定位算法;采用同态滤波增加图像前景与背景之间的亮度差异,同时利用改进的 Bersen算法,有效的将电表前景与背景分开;利用区域定位对图像进行粗定位,并对粗定位区域纵向投影,根据目标字符的纹理特征和先验知识对目标区域精确定位;经实验证明,该算法对其中四种电表图像的适应性良好.
Aiming at the specific application of automatic locating technology for ammeter number area, an automatic locating algorithm, which is suitable for four types of mechanical ammeter number area, is put forward. In order to enhance the lightness distinction between im-age foreground and backgrounds homomorphic filter is adopted, and improved Bersen algorithm is used to effectively separate the foreground and background of ammeter. First,use the method of area locating locate the probable area which is vertically projected then, and according to the texture of the target character and knowledge which is certified before, locate the target area to require a exact area. As the experi-ments proved, the algorithm has a fine adaptability of the image of four ammeters.