# -*- coding:gb2312 -*-import cv2from math import *import numpy as npimg = cv2.imread("3-2.jpg")height,width=img.shape[:2]degree=45#旋转后的尺寸heightNew=int(width*fabs(sin(radians(degree)))+height*fabs(cos(radians(degree))))widthNew=int(height*fabs(sin(radians(degree)))+width*fabs(cos(radians(degree))))matRotation=cv2.getRotationMatrix2D((width/2,height/2),degree,1)matRotation[0,2] +=(widthNew-width)/2 #重点在这步，目前不懂为什么加这步matRotation[1,2] +=(heightNew-height)/2 #重点在这步imgRotation=cv2.warpAffine(img,matRotation,(widthNew,heightNew),borderValue=(255,255,255))cv2.imshow("img",img)cv2.imshow("imgRotation",imgRotation)cv2.waitKey(0) 
