将机器视觉技术引入饮料瓶自动回收系统中.针对饮料瓶（PET材质）自身的特点，基于局部特征及几何不变性，采用一种亚像素级精度的角点提取方法，定义以角点为中心的左右曲线夹角及其符号作为饮料瓶的特征值，并提出基于“块”的快速匹配算法.实验结果表明，该算法具有较好的稳定性和可区分性，算法识别率高、速度快，能很好地满足饮料瓶自动识别回收的准确性和实时性要求.

In this work, the machine vision technique is introduced into an automated beverage bottle reclaiming system. Based on the characteristics of beverage bottles made of PET materials, local features and geometrical invariability, we extract the corner points at subpixel accuracy, define the curve angle around the central corner and its sign as the eigenvalues of a beverage bottle, and propose a blockmatching algorithm. Experimental results show that the algorithm is stable, and has good discrimination capability, high recognition rate and fast computation speed. It can meet the requirements of reclaiming beverage bottles accurately in real time.