At present, packaging line cannot identify the position and orientation of the particle packaging bag. It easily leaded to the appearance of the packaging bag folding, broken bags and leakage and other issues. In this paper,the image sensor was used to get the image of the packaging bag on the assembly line. The figure was processed by graying, median filtering and wavelet denoising. It was treated as binary images. The sobel operator was used to extract edge information of packaging bag. Four vertex and ce...