ROS2上使用WeChatQRdetector扫码二维码

微信的扫码算法对机器人在运动过程中产生的模糊、畸变有极强的识别率。ROS 2 社区有基于 OpenCV 编译的wechat_qrcode节点。功能包推荐ros2_wechat_qrcode或自行编写节点调用 OpenCV 的wechat_qrcode模块。工作流摄像头驱动节点发布图像话题Topic 扫码节点订阅并解析 发布识别到的字符串话题wechat_qrcode的主要功能实现依赖于detect.prototxtdetect.caffemodelsr.prototxtsr.caffemodel这样的四个模型文件。这四个文件可以在https://github.com/WeChatCV/opencv_3rdparty/tree/wechat_qrcode下载同时opencv官网也提供该函数的使用说明。整个文件夹架构ros2_ws/├─ src/│ └─ qrcode_detector/│ ├─ package.xml│ ├─ setup.py│ ├─ setup.cfg│ ├─ resource/│ │ └─ qrcode_detector│ ├─ qrcode_detector/│ │ ├─ __init__.py│ │ └─ qrcode_node.py│ ├─ launch/│ │ └─ qrcode_detector.launch.py│ └─ models/│ ├─ detect.prototxt│ ├─ detect.caffemodel│ ├─ sr.prototxt│ └─ sr.caffemodel将下载好的四个模型文件复制进models文件夹后然后在代码里用 ROS2 的 package share 路径读取关键是models/需要被安装到 ROS2 的share目录。你的setup.py里要加上from glob import glob import os setup( nameqrcode_detector, # ... data_files[ (share/ament_index/resource_index/packages, [resource/qrcode_detector]), (share/qrcode_detector, [package.xml]), (os.path.join(share, qrcode_detector, models), glob(models/*)), (os.path.join(share, qrcode_detector, launch), glob(launch/*.py)), ], )然后在节点文件里面拿到路径import os import cv2 as cv from ament_index_python.packages import get_package_share_directory pkg_share get_package_share_directory(qrcode_detector) model_dir os.path.join(pkg_share, models) detector cv.wechat_qrcode.WeChatQRCode( os.path.join(model_dir, detect.prototxt), os.path.join(model_dir, detect.caffemodel), os.path.join(model_dir, sr.prototxt), os.path.join(model_dir, sr.caffemodel), )最后再使用解码模块进行解码得到信息import os import cv2 as cv from ament_index_python.packages import get_package_share_directory import rclpy from rclpy.node import Node from sensor_msgs.msg import Image from cv_bridge import CvBridge pkg_share get_package_share_directory(line_follower_pkg) model_dir os.path.join(pkg_share, models) detector cv.wechat_qrcode.WeChatQRCode( os.path.join(model_dir, detect.prototxt), os.path.join(model_dir, detect.caffemodel), os.path.join(model_dir, sr.prototxt), os.path.join(model_dir, sr.caffemodel), ) class WeChatQR(Node): def __init__(self): super().__init__(wechat_qr) self.bridge CvBridge() self.subscription self.create_subscription( Image, your topic, self.image_callback, 10 ) self.subscription # prevent unused variable warning def image_callback(self, msg): cv_image self.bridge.imgmsg_to_cv2(msg, desired_encodingbgr8) decoded_info, points detector.detectAndDecode(cv_image) if decoded_info: for info in decoded_info: self.get_logger().info(fDecoded QR Code: {info}) def destroy_node(self): self.cap.release() super().destroy_node() def main(argsNone): rclpy.init(argsargs) node WeChatQR() try: rclpy.spin(node) except KeyboardInterrupt: pass finally: node.destroy_node() rclpy.shutdown() if __name__ __main__: main()