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mrbemani/cv_calib_mono.py

Created July 5, 2020 05:54
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calibrate mono camera using opencv
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cv_calib_mono.py
# -*- coding: utf-8 -*-
__author__ = 'Shi Qi'
import sys
import os
import argparse
import json
import numpy as np
import cv2
from decimal import Decimal
def str2bool(v):
if v.lower() in ('yes', 'true', 't', 'y', '1'):
return True
elif v.lower() in ('no', 'false', 'f', 'n', '0'):
return False
else:
raise argparse.ArgumentTypeError('Boolean value expected.')
def deci(n):
return '%.16e' % Decimal(n)
def get_checkerboard_points(w, h, objp, images, imw=800, winname="Camera Checkerboard View"):
# 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.
objpoints = [] # 3d point in real world space
imgpoints = [] # camera 2d points in image plane.
for fname in images:
img = cv2.imread(fname)
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
# Find the chess board corners
ret, corners = cv2.findChessboardCorners(gray, (w,h), None)
# If found, add object points, image points (after refining them)
if ret is True:
objpoints.append(objp)
corners2=cv2.cornerSubPix(gray,corners, (11,11), (-1,-1), criteria)
imgpoints.append(corners)
# Draw and display the corners
cv2.drawChessboardCorners(img, (w,h), corners2, ret)
ih, iw = gray.shape
nw = imw
nh = int(float(ih) / float(iw) * float(nw))
ims = cv2.resize(img, (nw, nh))
cv2.imshow(winname, ims)
k = cv2.waitKey(100)
if k == 27:
break
return objpoints, imgpoints
def calibrate_mono_camera(cwh, camdir, outfile):
w, h = cwh
imgs = []
if os.path.isdir(camdir):
imgs = [os.path.join(camdir, p) for p in os.listdir(camdir) if p.lower().endswith('.jpg') or p.lower().endswith('.png')]
else:
print ("[ERROR] camdir does not exist!")
return (1, None)
if len(imgs) < 2:
print ("[ERROR] Images are empty.")
return (2, None)
imh, imw = cv2.imread(imgs[0]).shape[:2]
imsize = (imw, imh)
imgpoints = []
objpoints = []
objp = np.zeros((h*w,3), np.float32)
objp[:,:2] = np.mgrid[0:w,0:h].T.reshape(-1,2)
r = get_checkerboard_points(w, h, objp, imgs, 800)
if r is not None:
objpoints, imgpoints = r
else:
return (3, None)
# camMatrix = np.zeros((3, 3), np.float32)
# camMatrix[0,0] = 1.0
# camMatrix[1,1] = 1.0
camMatrix = cv2.initCameraMatrix2D(objpoints, imgpoints, imsize)
print ("initial camMatrix: \n{}".format(camMatrix))
camDist = np.zeros(8, dtype=np.float32)
retval, camMatrix, camDist, rvecs, tvecs = cv2.calibrateCamera(objpoints, imgpoints, imsize, camMatrix, camDist, flags=0)
#retval, camMatrix, camDist, rvecs, tvecs = cv2.calibrateCamera(objpoints, imgpoints, imsize, camMatrix, camDist, flags=flags)
print ("===")
print ("retval: {}".format(retval))
print ("Intrinsics: {}".format(camMatrix))
print ("Distortion: {}".format(camDist))
print ("===")
if outfile is not None:
print ("Saving...")
cv_file = cv2.FileStorage(outfile, cv2.FILE_STORAGE_WRITE)
#cv_file.write("retval", retval)
cv_file.write("Intrinsics", camMatrix)
cv_file.write("Distortion", camDist)
cv_file.release()
print ("Done saving.")
return (0, (retval, camMatrix, camDist, rvecs, tvecs))
def undistort_image(i_im, o_im, k, d):
im = cv2.imread(i_im)
ih, iw = im.shape[:2]
# newk, roi = cv2.getOptimalNewCameraMatrix(k, d, (ih, iw), 1, (ih, iw))
# print (newk)
# print (roi)
# crop the image
# x, y, w, h = roi
# undistort
dst = cv2.undistort(im, k, d, None, k)
#dst = dst[y:y+h, x:x+w]
cv2.imwrite(o_im, dst)
def main(args):
if type(args) is not argparse.Namespace:
print ("[ERROR] Invalid Command-line parameters!")
return 1
ret = 0
if args.mode == "calib":
if args.checkerboard is None or len(args.checkerboard) != 2:
print ("[ERROR] Invalid --checkerboard. Should be in the form: WxH")
return 2
checkerboardWH = args.checkerboard
cam_input_dir = os.path.abspath(args.camera_dir)
cam_out_dir = os.path.abspath(args.output_params_dir)
if not os.path.isdir(cam_input_dir):
print ("Error: {} does not exist!".format(args.camera_dir))
return 1
if not os.path.isdir(cam_out_dir):
os.mkdir(cam_out_dir)
camdirs = [x for x in os.listdir(cam_input_dir) if os.path.isdir(os.path.join(cam_input_dir, x))]
totalcams = len(camdirs)
donecams = 0
cams = []
for camdir in camdirs:
print ("[{} / {}] Calibrating: {} ...".format(donecams+1, totalcams, camdir))
r, cam = calibrate_mono_camera(checkerboardWH, os.path.join(cam_input_dir, camdir), os.path.join(cam_out_dir, "{}.xml".format(camdir)))
if r != 0:
print ("Failed: {}".format(camdir))
else:
donecams += 1
cams.append(cam)
print ("\nCameras calibrated: {} in {}.\n".format(donecams, totalcams))
elif args.mode == "undistort":
imgdir = os.path.abspath(args.images_dir)
unddir = os.path.abspath(args.undistorted_dir)
camfile = os.path.abspath(args.input_camera_params_file)
k = None
d = None
if not os.path.isfile(camfile):
print ("Error: input camera parameters file is invalid.")
return 1
else:
k_file = cv2.FileStorage(camfile, cv2.FILE_STORAGE_READ)
k = k_file.getNode("Intrinsics").mat()
d = k_file.getNode("Distortion").mat()
if not os.path.isdir(imgdir):
print ("Error: input images_dir is invalid.")
return 2
if not os.path.isdir(unddir):
os.mkdir(unddir)
imgs = [p for p in os.listdir(imgdir) if p.lower().endswith('.jpg') or p.lower().endswith('.png')]
total_img = len(imgs)
if total_img < 1:
print("No Image for undistorting.")
return 3
und_img = 0
for im in imgs:
opimg = os.path.join(imgdir, im)
print ("[{} / {}] Undistorting Image: {} ...".format(und_img+1, total_img, opimg))
undistort_image(opimg, os.path.join(unddir, im), k, d)
und_img += 1
print ("\nDone!\nImages undistorted: {} in {}.\n".format(und_img, total_img))
else:
print ("Error: Invalid --mode. only calib and undistort are implemented.")
return 2
return ret
if __name__ == '__main__':
parser = argparse.ArgumentParser(description='Monno-Camera Calibration.')
parser.add_argument('-b', '--checkerboard', type=lambda s: [int(x) for x in s.split('x')], help="checkerboard resolution. in the form: WxH")
parser.add_argument('-c', '--camera_dir', type=str, help="camera image directory. it should contain camera subdirs which themselves contain JPEGs or PNGs.")
parser.add_argument('-o', '--output_params_dir', type=str, help="output directory to store camera parameters.")
parser.add_argument('-m', '--mode', type=str, default="calib", help="script mode, calib | undistort. default: calib")
parser.add_argument('-k', '--input_camera_params_file', type=str, help="only for undistort. path to camera parameters XML file.")
parser.add_argument('-i', '--images_dir', type=str, help="only for undistort. input images to undistort", )
parser.add_argument('-u', '--undistorted_dir', type=str, help="only for undistort. output undistorted images", default="undistorted")
args = parser.parse_args()
print ("\n=== Start ===\n")
ret = main(args)
if ret == 0:
print ("\n=== Done ===\n")
else:
print ("\n[ERROR] Program ended unexpectedly! Errno: {}\n".format(ret))
print ("\n=== Failed ===\n")
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