随手笔记——将ROS图像话题转为OpenCV图像格式处理后再转为ROS图像话题发布（Python版）

说明

将ROS图像话题转为OpenCV图像格式处理后再转为ROS图像话题发布，主要通过CvBridge的cv2_to_imgmsg和imgmsg_to_cv2函数（Python版）。

关键函数

imgmsg_to_cv2将图像从ROS消息格式转换成OpenCV格式
cv2_to_imgmsg 将数据转成ROS消息格式

代码

#!/usr/bin/env python
# -*- coding: utf-8 -*-import rospy
import cv2
from cv_bridge import CvBridge, CvBridgeError
from sensor_msgs.msg import Imageclass image_converter:def __init__(self):    # 创建cv_bridge，声明图像的发布者和订阅者self.image_pub = rospy.Publisher("cv_bridge_image", Image, queue_size=1)self.bridge = CvBridge()self.image_sub = rospy.Subscriber("/usb_cam/image_raw", Image, self.callback)def callback(self,data):# 使用cv_bridge将ROS的图像数据转换成OpenCV的图像格式try:cv_image = self.bridge.imgmsg_to_cv2(data, "bgr8")except CvBridgeError as e:print e# 在opencv的显示窗口中绘制一个圆，作为标记(rows,cols,channels) = cv_image.shapeif cols > 60 and rows > 60 :cv2.circle(cv_image, (60, 60), 30, (0,0,255), -1)# 显示Opencv格式的图像cv2.imshow("Image window", cv_image)cv2.waitKey(3)# 再将opencv格式额数据转换成ros image格式的数据发布try:self.image_pub.publish(self.bridge.cv2_to_imgmsg(cv_image, "bgr8"))except CvBridgeError as e:print eif __name__ == '__main__':try:# 初始化ros节点rospy.init_node("cv_bridge_test")rospy.loginfo("Starting cv_bridge_test node")image_converter()rospy.spin()except KeyboardInterrupt:print "Shutting down cv_bridge_test node."cv2.destroyAllWindows()

注：代码来自古月，如有侵权，请联系删除！