cv2 surf

本篇博客主要介绍cv2模块中的surf，即加速版的SIFT。

示例代码：

# encoding:utf-8
import cv2
import matplotlib.pyplot as plt
 
img = cv2.imread('../data/butterfly.jpg', 0)
surf = cv2.xfeatures2d.SURF_create(400)
 
kp, des = surf.detectAndCompute(img, None)
 
print(surf.getHessianThreshold())
 
surf.setHessianThreshold(50000)
 
kp, des = surf.detectAndCompute(img, None)
 
img2 = cv2.drawKeypoints(img, kp, None, (255, 0, 0), 4)
 
plt.imshow(img2)
plt.show()
 
print(surf.descriptorSize())
 
print(surf.getExtended())
surf.setExtended(True)
kp, des = surf.detectAndCompute(img, None)
print(surf.descriptorSize())
print(des.shape)

测试图像：