The first section of the Python code is given in the following code fragment. It mainly involves importing rospy, sys, cv2, sensor_msgs, cv_bridge, and the numpy module. The sensor_msgs dependency imports the ROS data type of both image and camera information type. The cv_bridge module imports the CvBridge class for converting the ROS image data type to the OpenCV data type and vice versa:
import rospyimport sysimport cv2from sensor_msgs.msg import Image, CameraInfofrom cv_bridge import CvBridge, CvBridgeErrorfrom std_msgs.msg import Stringimport numpy as np
The following section of code is a class definition in Python that we will use to demonstrate CvBridge functions. The class is ...