rainbowpolar

I am trying to calibrate camera using OpenCV tools according to the following. The problem is that function findChessboardCorners cannot find any chessboard on images I tried.

I used a lot of them - even just plain chessboard pattern. In any case, nothing was detected. Here is the code (almost the same as from link above): import numpy as np import cv2 import glob # termination criteria criteria = (cv2. Download Game Asphalt 7 Untuk Windows Phone 8. Acronis Backup For Vmware Cracked. TERM_CRITERIA_EPS + cv2.TERM_CRITERIA_MAX_ITER, 30, 0.001) # prepare object points, like (0,0,0), (1,0,0), (2,0,0).,(6,5,0) objp = np.zeros((6*7,3), np.float32) objp[:,:2] = np.mgrid[0:7,0:6].T.reshape(-1,2) # Arrays to store object points and image points from all the images. Objpoints = [] # 3d point in real world space imgpoints = [] # 2d points in image plane. Just for other Python newbies that may go down this road.

Working code: import numpy as np import cv2 import glob # termination criteria criteria = (cv2.TERM_CRITERIA_EPS + cv2.TERM_CRITERIA_MAX_ITER, 30, 0.001) # Arrays to store object points and image points from all the images. Imgpoints = [] # 2d points in image plane. Images = glob.glob('*.png') for fname in images: img = cv2.imread(fname) gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY) ret = False # Find the chess board corners ret, corners = cv2.findChessboardCorners(gray, (7,7)) # If found, add object points, image points (after refining them) if ret == True: cv2.cornerSubPix(gray, corners, (11,11), (-1,-1), criteria) imgpoints.append(corners) # Draw and display the corners cv2.drawChessboardCorners(img, (7,7), corners, ret) cv2.imshow('img',img) cv2.waitKey(0) cv2.destroyAllWindows() Two main points: • You have to carefully count dimension of you pattern. (7,7) is for usual chessboard.

Tutorial Camera Calibration. Jump to: navigation. Download, and print; Mount the. Chessboard patterns tend to produce slightly more accurate results.

• Line img = cv2.drawChessboardCorners(img, (7,6), corners2,ret) doesn't work, you have to change it to cv2.drawChessboardCorners(img, (7,6), corners2,ret) (function doesn't return image). Thanks to AldurDisciple!