python opencv实现任意角度的透视变换实例代码

# -*- coding:utf-8 -*-import cv2import numpy as npdef rad(x):  return x * np.pi / 180img = cv2.imread("6.jfif")cv2.imshow("original", img)# 扩展图像，保证内容不超出可视范围img = cv2.copyMakeBorder(img, 200, 200, 200, 200, cv2.BORDER_CONSTANT, 0)w, h = img.shape[0:2]anglex = 0angley = 30anglez = 0 #是旋转fov = 42while 1:  # 镜头与图像间的距离，21为半可视角，算z的距离是为了保证在此可视角度下恰好显示整幅图像  z = np.sqrt(w ** 2 + h ** 2) / 2 / np.tan(rad(fov / 2))  # 齐次变换矩阵  rx = np.array([[1, 0, 0, 0],          [0, np.cos(rad(anglex)), -np.sin(rad(anglex)), 0],          [0, -np.sin(rad(anglex)), np.cos(rad(anglex)), 0, ],          [0, 0, 0, 1]], np.float32)  ry = np.array([[np.cos(rad(angley)), 0, np.sin(rad(angley)), 0],          [0, 1, 0, 0],          [-np.sin(rad(angley)), 0, np.cos(rad(angley)), 0, ],          [0, 0, 0, 1]], np.float32)  rz = np.array([[np.cos(rad(anglez)), np.sin(rad(anglez)), 0, 0],          [-np.sin(rad(anglez)), np.cos(rad(anglez)), 0, 0],          [0, 0, 1, 0],          [0, 0, 0, 1]], np.float32)  r = rx.dot(ry).dot(rz)  # 四对点的生成  pcenter = np.array([h / 2, w / 2, 0, 0], np.float32)  p1 = np.array([0, 0, 0, 0], np.float32) - pcenter  p2 = np.array([w, 0, 0, 0], np.float32) - pcenter  p3 = np.array([0, h, 0, 0], np.float32) - pcenter  p4 = np.array([w, h, 0, 0], np.float32) - pcenter  dst1 = r.dot(p1)  dst2 = r.dot(p2)  dst3 = r.dot(p3)  dst4 = r.dot(p4)  list_dst = [dst1, dst2, dst3, dst4]  org = np.array([[0, 0],          [w, 0],          [0, h],          [w, h]], np.float32)  dst = np.zeros((4, 2), np.float32)  # 投影至成像平面  for i in range(4):    dst[i, 0] = list_dst[i][0] * z / (z - list_dst[i][2]) + pcenter[0]    dst[i, 1] = list_dst[i][1] * z / (z - list_dst[i][2]) + pcenter[1]  warpR = cv2.getPerspectiveTransform(org, dst)  result = cv2.warpPerspective(img, warpR, (h, w))  cv2.imshow("result", result)  c = cv2.waitKey(30)  # anglex += 3      #auto rotate  # anglez += 1       #auto rotate  # angley += 2      #auto rotate  # 键盘控制  if 27 == c: # Esc quit    break;  if c == ord('w'):    anglex += 1  if c == ord('s'):    anglex -= 1  if c == ord('a'):    angley += 1    # dx=0  if c == ord('d'):    angley -= 1  if c == ord('u'):    anglez += 1  if c == ord('p'):    anglez -= 1  if c == ord('t'):    fov += 1  if c == ord('r'):    fov -= 1  if c == ord(' '):    anglex = angley = anglez = 0  if c == ord('q'):    print("======================================")    print('旋转矩阵：/n', r)    print("angle alpha: ", anglex, 'angle beta: ', angley, "dz: ", anglez, ": ", z)cv2.destroyAllWindows()