Camera calibration opencv python

Question

I am following the OpenCV tutorial http://opencv-python-tutroals.readthedocs.io/en/latest/py_tutorials/py_calib3d/py_calibration/py_calibration.html

Instead of running it with a chess board, I got my 3D point coordinates from a LAS file. Here is my code:

import cv2
import numpy as np

obj_point = [(630931.35,4833642.85,157.67),(630948.03,4833662.76,73.94), (631156.3, 4833904.18, 43.89),(630873.71, 4833790, 44.85), (631381.3, 4834152.6, 79.41)]
img_point = [(1346.82,843.206),(1293.03,808.146),(1041.92, 585.168), (1150.21, 894.724), (756.993,345.904) ]

obj_point = np.array(obj_point,'float32')
img_point = np.array(img_point,'float32')

ret, mtx, dist, rvecs, tvecs = cv2.calibrateCamera(obj_point, img_point, (1125, 1725),None,None) 

I got the following error message:

For non-planar calibration rigs the initial intrinsic matrix must be specified in function cvCalibrateCamera2

Thx in advance!

Answer 1

You need to use the flag CV_CALIB_USE_INTRINSIC_GUESS