Ask Your Question
0

input arguments of python's cv2.calibrateCamera

asked 2015-03-30 12:31:51 -0600

krips89 gravatar image

I get the following error when I try to calibrate camera using cv2.calibrateCamera:

rms, camera_matrix, dist_coefs, rvecs, tvecs = cv2.calibrateCamera(pts3d, pts2d, self.imgsize, None, None)
cv2.error: /home/sarkar/opencv/opencv/modules/calib3d/src/calibration.cpp:2976: error: (-210) objectPoints should contain vector of vectors of points of type Point3f in function collectCalibrationData

I initially had nx3 and nx2 array for pts3d and pts2d. I then tried to reshape pts3d and pts2d in the following form as the function takes vectors of vector point3d (and correspondingly pts2d) as input:

[1 x n x 3] and [1 x n x 2]

[k x n' x 3] and [k x n' x 3], where k is some random value

[1 x n x 1 x 3] and [1 x n x 1 x 2]

nothing works and it always gives the same error.

I saw the code sample code of cameraclibration provided which runs fine, and their input is of [k x n x 3]. I really don't know what is wrong with my implementation. Following is my code to be precise:

   #data contains [n x 5] dim array which is the hstacked arrays of pts3d and pts2d correspondences I obtained elsewhere. 
    pts3d = data[:, 0:3] #first 3 column 
    pts2d = data[:, 3:5] #next 2 column.. I checked the values are coming correctly 
    pts3d = pts3d.reshape(1,-1, 3) #Here, I have experimented by resizing with different values. 
    pts2d = pts2d.reshape(1,-1, 2)

    rms, camera_matrix, dist_coefs, rvecs, tvecs = cv2.calibrateCamera(pts3d, pts2d, self.imgsize, None, None)

the error happens at the time of the function call. It would be nice to know what can be wrong here.

edit retag flag offensive close merge delete

1 answer

Sort by ยป oldest newest most voted
0

answered 2018-03-06 08:47:10 -0600

abhijit gravatar image

The Points must be of type np.float32. Also you can check out this small python API which you can use to calibrate the camera using opencv.

edit flag offensive delete link more

Comments

Thanks, that helps.

klimenkov gravatar imageklimenkov ( 2019-04-02 10:59:24 -0600 )edit

Question Tools

1 follower

Stats

Asked: 2015-03-30 12:31:51 -0600

Seen: 4,927 times

Last updated: Mar 06 '18