def calibration(extrinsic_matrix, cam_intrinsics, device_frame_from_road_frame=None):
if device_frame_from_road_frame is None:
device_frame_from_road_frame = np.hstack((np.diag([1, -1, -1]), [[0], [0], [1.51]]))
med_frame_from_ground = medmodel_intrinsics@view_frame_from_device_frame@device_frame_from_road_frame[:,(0,1,3)]
ground_from_med_frame = np.linalg.inv(med_frame_from_ground)
extrinsic_matrix_eigen = extrinsic_matrix[:3]
camera_frame_from_road_frame = np.dot(cam_intrinsics, extrinsic_matrix_eigen)
camera_frame_from_ground = np.zeros((3,3))
camera_frame_from_ground[:,0] = camera_frame_from_road_frame[:,0]
camera_frame_from_ground[:,1] = camera_frame_from_road_frame[:,1]
camera_frame_from_ground[:,2] = camera_frame_from_road_frame[:,3]
warp_matrix = np.dot(camera_frame_from_ground, ground_from_med_frame)
return warp_matrix
这个函数能讲解下吗？ 我大概明白这是相机到虚拟相机的转换矩阵计算