说明：  1拍摄一张包含两本成一定夹角放置的书的图像2获得书的边缘二值图像3通过hough变换在原始灰度图像中用红色标记出书的边缘，计算两本书的夹角
(1 shot 1 into a certain angle contains two books placed on the edge of the image 2 receive the binary image 3 by hough transform the original gray image using the red mark the edge of a book to calculate the angle between the two books)