The following code produce the error (cv2 on Python 2.7):
error: (-215) npoints >= 0 && npoints == std::max(ipoints.checkVector(2, CV_32F), ipoints.checkVector(2, CV_64F)) in function solvePnP
I can't figure out why.
This is the code:
import os, sys
import math
import numpy as np
import cv2
img_file = os.path.join(img_folder,'1.jpg')
img = cv2.imread(img_file,0)
h,w = img.shape
obj_pts = np.array([[10,60,0],
[10,60,12.6],
[24,60,0],
[24,60,12.6],
[24,74,0],
[24,74,12.6],
[30,70,0],
[30,70,8.8],
[47.7,70,0],
[47.7,70,8.8]
], dtype=np.float32)
img_pts = np.array([[800,970],
[689,329],
[1380,1175],
[1363,458],
[1842,881],
[1875,256],
[1977,1051],
[1994,592],
[2959,1347],
[3052,852]
], dtype=int)
img_pts = np.fliplr(img_pts)
if True:
ppa = (w/2., h/2.)
fm = 7.5/1e3
sensor = (7.14e-3, 5.36e-3)
focal = w* (fm / sensor[0])
cam_mat = np.array( [[focal, 0, ppa[0]],
[0, focal, ppa[1]],
[0, 0, 1]], dtype = np.float64
)
dist_coeffs = np.zeros((5,1))
rvec = np.zeros((3,1))
tvec = np.zeros((3,1))
flag = cv2.SOLVEPNP_ITERATIVE # tried with SOLVEPNP_EPNP, same error.
retval, rvec, tvec = cv2.solvePnP(obj_pts, img_pts, cam_mat, dist_coeffs, rvec, tvec, flags=flag)