#!/usr/bin/env python import rospy import cv2 as cv import numpy as np from cv_bridge import CvBridge, CvBridgeError from sensor_msgs.msg import Image import tf from tf.broadcaster import TransformBroadcaster import tf_conversions from mycobot_communication.srv import ( GetCoords, SetCoords, GetAngles, SetAngles, GripperStatus, ) class ImageConverter: def __init__(self): self.br = TransformBroadcaster() self.bridge = CvBridge() self.aruco_dict = cv.aruco.Dictionary_get(cv.aruco.DICT_6X6_250) self.aruo_params = cv.aruco.DetectorParameters_create() calibrationParams = cv.FileStorage( "calibrationFileName.xml", cv.FILE_STORAGE_READ ) self.dist_coeffs = calibrationParams.getNode("distCoeffs").mat() self.camera_matrix = None self.image_sub = rospy.Subscriber("/camera/image", Image, self.callback) def callback(self, data): """Callback function. Process image with OpenCV, detect Mark to get the pose. Then acccording the pose to transforming. """ try: cv_image = self.bridge.imgmsg_to_cv2(data, "bgr8") except CvBridgeError as e: print(e) size = cv_image.shape focal_length = size[1] center = [size[1] / 2, size[0] / 2] if self.camera_matrix is None: self.camera_matrix = np.array( [ [focal_length, 0, center[0]], [0, focal_length, center[1]], [0, 0, 1], ], dtype=np.float32, ) gray = cv.cvtColor(cv_image, cv.COLOR_BGR2GRAY) corners, ids, rejectImaPoint = cv.aruco.detectMarkers( gray, self.aruco_dict, parameters=self.aruo_params ) if len(corners) > 0: if ids is not None: # print('corners:', corners, 'ids:', ids) ret = cv.aruco.estimatePoseSingleMarkers( corners, 0.05, self.camera_matrix, self.dist_coeffs ) (rvec, tvec) = (ret[0], ret[1]) (rvec - tvec).any() print("rvec:", rvec, "tvec:", tvec) for i in range(rvec.shape[0]): cv.aruco.drawDetectedMarkers(cv_image, corners) cv.aruco.drawAxis( cv_image, self.camera_matrix, self.dist_coeffs, rvec[i, :, :], tvec[i, :, :], 0.03, ) # Just process first one detected. xyz = tvec[0, 0, :] xyz = [xyz[0] - 0.045, xyz[1], xyz[2] - 0.03] euler = rvec[0, 0, :] tf_change = tf.transformations.quaternion_from_euler( euler[0], euler[1], euler[2] ) print("tf_change:", tf_change) self.br.sendTransform( xyz, tf_change, rospy.Time.now(), "basic_shapes", "joint6_flange" ) # [x, y, z, -172, 3, -46.8] cv.imshow("Image", cv_image) cv.waitKey(3) try: pass except CvBridgeError as e: print(e) if __name__ == "__main__": try: rospy.init_node("detect_marker") rospy.loginfo("Starting cv_bridge_test node") ImageConverter() rospy.spin() except KeyboardInterrupt: print("Shutting down cv_bridge_test node.") cv.destroyAllWindows()