Initial commit

.gitignore

@@ -0,0 +1 @@
+results/

.idea/.gitignore

@@ -0,0 +1,3 @@
+# Default ignored files
+/shelf/
+/workspace.xml

.idea/cam_pose.iml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="PYTHON_MODULE" version="4">
+  <component name="NewModuleRootManager">
+    <content url="file://$MODULE_DIR$" />
+    <orderEntry type="jdk" jdkName="Python 3.12 virtualenv at ~/work/chromakey/.venv" jdkType="Python SDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

.idea/inspectionProfiles/profiles_settings.xml

@@ -0,0 +1,6 @@
+<component name="InspectionProjectProfileManager">
+  <settings>
+    <option name="USE_PROJECT_PROFILE" value="false" />
+    <version value="1.0" />
+  </settings>
+</component>

.idea/misc.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Black">
+    <option name="sdkName" value="Python 3.12 virtualenv at ~/work/chromakey/.venv" />
+  </component>
+</project>

.idea/modules.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/cam_pose.iml" filepath="$PROJECT_DIR$/.idea/cam_pose.iml" />
+    </modules>
+  </component>
+</project>

README.md

@@ -0,0 +1,2 @@
+https://docs.opencv.org/4.x/d6/d55/tutorial_table_of_content_calib3d.html
+https://docs.opencv.org/4.x/d9/db7/tutorial_py_table_of_contents_calib3d.html

cam_calib.py

@@ -0,0 +1,77 @@
+import numpy as np
+import cv2 as cv
+import glob
+
+def main():
+	# termination criteria
+	criteria = (cv.TERM_CRITERIA_EPS + cv.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.
+
+	images = glob.glob('*.jpg')
+
+	for fname in images:
+		img = cv.imread(fname)
+		gray = cv.cvtColor(img, cv.COLOR_BGR2GRAY)
+
+		# Find the chess board corners
+		ret, corners = cv.findChessboardCorners(gray, (7, 6), None)
+
+		# If found, add object points, image points (after refining them)
+		if ret:
+			objpoints.append(objp)
+
+			corners2 = cv.cornerSubPix(gray, corners, (11, 11), (-1, -1), criteria)
+			imgpoints.append(corners2)
+
+			# Draw and display the corners
+			cv.drawChessboardCorners(img, (7, 6), corners2, ret)
+			cv.imshow('img', img)
+			cv.waitKey(500)
+
+		#  Calibration
+		ret, mtx, dist, rvecs, tvecs = cv.calibrateCamera(objpoints, imgpoints, gray.shape[::-1], None, None)
+
+		# write to file
+		np.savez("results/cam.npz", mtx=mtx, dist=dist, rvecs=rvecs, tvecs=tvecs)
+
+		#  Undistortion
+		img = cv.imread('checker_cam.jpg')
+		h, w = img.shape[:2]
+		newcameramtx, roi = cv.getOptimalNewCameraMatrix(mtx, dist, (w, h), 1, (w, h))
+
+		#  1. Using cv.undistort()
+		dst = cv.undistort(img, mtx, dist, None, newcameramtx)
+
+		# crop the image
+		x, y, w, h = roi
+		dst = dst[y:y + h, x:x + w]
+		cv.imwrite('results/calibresult_1.png', dst)
+
+		# 2. Undistort using remapping
+		mapx, mapy = cv.initUndistortRectifyMap(mtx, dist, None, newcameramtx, (w, h), 5)
+		dst = cv.remap(img, mapx, mapy, cv.INTER_LINEAR)
+
+		# crop the image
+		x, y, w, h = roi
+		dst = dst[y:y + h, x:x + w]
+		cv.imwrite('results/calibresult_2.png', dst)
+
+		#  Re-projection Error
+		mean_error = 0
+		for i in range(len(objpoints)):
+			imgpoints2, _ = cv.projectPoints(objpoints[i], rvecs[i], tvecs[i], mtx, dist)
+			error = cv.norm(imgpoints[i], imgpoints2, cv.NORM_L2) / len(imgpoints2)
+			mean_error += error
+
+		print("total error: {}".format(mean_error / len(objpoints)))
+	cv.destroyAllWindows()
+
+if __name__ == '__main__':
+	main()

cam_pose.py

@@ -0,0 +1,99 @@
+import numpy as np
+import cv2 as cv
+import glob
+
+def draw_gizmo(img, corners, imgpts):
+	corner = tuple(corners[0].ravel().astype("int32"))
+	imgpts = imgpts.astype("int32")
+	img = cv.line(img, corner, tuple(imgpts[0].ravel()), (255,0,0), 5)
+	img = cv.line(img, corner, tuple(imgpts[1].ravel()), (0,255,0), 5)
+	img = cv.line(img, corner, tuple(imgpts[2].ravel()), (0,0,255), 5)
+	return img
+
+
+def draw_cube(img, corners, imgpts):
+	imgpts = np.int32(imgpts).reshape(-1, 2)
+
+	# draw ground floor in green
+	img = cv.drawContours(img, [imgpts[:4]], -1, (0, 255, 0), -3)
+
+	# draw pillars in blue color
+	for i, j in zip(range(4), range(4, 8)):
+		img = cv.line(img, tuple(imgpts[i]), tuple(imgpts[j]), (255), 3)
+
+	# draw top layer in red color
+	img = cv.drawContours(img, [imgpts[4:]], -1, (0, 0, 255), 3)
+
+	return img
+
+
+def main():
+	process_video()
+
+def process_video():
+	with np.load('results/cam.npz') as X:
+		mtx, dist, _, _ = [X[i] for i in ('mtx', 'dist', 'rvecs', 'tvecs')]
+
+	criteria = (cv.TERM_CRITERIA_EPS + cv.TERM_CRITERIA_MAX_ITER, 30, 0.001)
+	objp = np.zeros((6 * 7, 3), np.float32)
+	objp[:, :2] = np.mgrid[0:7, 0:6].T.reshape(-1, 2)
+
+	axis = np.float32([[3, 0, 0], [0, 3, 0], [0, 0, -3]]).reshape(-1, 3)
+
+	# Open camera
+	video = cv.VideoCapture(0)
+	if not video.isOpened():
+		print("Cannot open camera")
+		exit()
+
+	while True:
+		# Read a new frame
+		ok, img = video.read()
+		if not ok:
+			return
+		process_img(img, criteria, objp, axis, mtx, dist)
+		k = cv.waitKey(1) & 0xFF
+		if k == ord('q'):
+			break
+
+def process_still():
+	with np.load('results/cam.npz') as X:
+		mtx, dist, _, _ = [X[i] for i in ('mtx', 'dist', 'rvecs', 'tvecs')]
+
+	criteria = (cv.TERM_CRITERIA_EPS + cv.TERM_CRITERIA_MAX_ITER, 30, 0.001)
+	objp = np.zeros((6 * 7, 3), np.float32)
+	objp[:, :2] = np.mgrid[0:7, 0:6].T.reshape(-1, 2)
+
+	axis = np.float32([[3, 0, 0], [0, 3, 0], [0, 0, -3]]).reshape(-1, 3)
+
+	for fname in glob.glob('check*.jpg'):
+		img = cv.imread(fname)
+		process_img(img, criteria, objp, axis, mtx, dist)
+		k = cv.waitKey(1) & 0xFF
+		if k == ord('q'):
+			break
+
+
+def process_img(img, criteria, objp, axis, mtx, dist):	# Load previously saved data
+	pattern_size = (7, 6)
+	gray = cv.cvtColor(img, cv.COLOR_BGR2GRAY)
+	ret, corners = cv.findChessboardCorners(gray, pattern_size, corners=None, flags=cv.CALIB_CB_ADAPTIVE_THRESH+cv.CALIB_CB_NORMALIZE_IMAGE)
+	cv.drawChessboardCorners(img, corners=corners, patternSize=pattern_size, patternWasFound=ret)
+
+	if ret:
+		corners2 = cv.cornerSubPix(gray, corners, (11, 11), (-1, -1), criteria)
+
+		# Find the rotation and translation vectors.
+		ret, rvecs, tvecs = cv.solvePnP(objp, corners2, mtx, dist)
+
+		# project 3D points to image plane
+		imgpts, jac = cv.projectPoints(axis, rvecs, tvecs, mtx, dist)
+
+		img = draw_gizmo(img, corners2, imgpts)
+
+	cv.imshow('img', img)
+
+
+if __name__ == '__main__':
+	main()
+	cv.destroyAllWindows()