mi-task/basic_motion/camera.py

#!/usr/bin/env python3bu
import rclpy
from rclpy.node import Node
from sensor_msgs.msg import Image
from cv_bridge import CvBridge
from rclpy.qos import qos_profile_sensor_data, QoSProfile, ReliabilityPolicy
import cv2
import numpy as np
import matplotlib.pyplot as plt
from datetime import datetime

class MiroCameraROS2(Node):
    def __init__(self):
        """初始化ROS 2节点和相机订阅者"""
        super().__init__('miro_camera_node')
        
        # 创建CV桥接器，用于ROS图像消息和OpenCV图像之间的转换
        self.bridge = CvBridge()
        
        # 存储相机图像的变量
        self.image = None
        
        # 声明参数
        self.declare_parameter('namespace', '')
        self.declare_parameter('camera_topic', '/rgb_camera/image_raw')
        
        # 获取参数值
        self.namespace = self.get_parameter('namespace').get_parameter_value().string_value
        self.camera_topic = self.get_parameter('camera_topic').get_parameter_value().string_value
        
        # 构建完整话题名称
        self.full_topic = f"{self.namespace}{self.camera_topic}"
        
        # 创建与相机发布者匹配的QoS配置（BEST_EFFORT）
        qos = QoSProfile(
            reliability=ReliabilityPolicy.BEST_EFFORT,  # 与相机驱动保持一致
            history=qos_profile_sensor_data.history,   # 保留sensor_data的其他配置
            depth=qos_profile_sensor_data.depth
        )
        
        # 订阅相机图像话题，使用BEST_EFFORT QoS配置
        self.image_sub = self.create_subscription(
            Image,
            self.full_topic,
            self.image_callback,
            qos
        )
        
        self.get_logger().info(f"正在监听话题: {self.full_topic}")
        self.get_logger().info(f"使用QoS配置: Reliability={qos.reliability.name}, Depth={qos.depth}")
        
    def image_callback(self, data):
        """处理相机图像消息"""
        try:
            # 将ROS图像消息转换为OpenCV格式（BGR）
            cv_image = self.bridge.imgmsg_to_cv2(data, 'bgr8')
            # 转换为RGB格式
            self.image = cv2.cvtColor(cv_image, cv2.COLOR_BGR2RGB)
        except Exception as e:
            self.get_logger().error(f'处理相机图像时出错: {e}')
    
    def get_latest_image(self, timeout_sec=5.0):
        """获取最新的相机图像，带超时机制"""
        start_time = self.get_clock().now().nanoseconds * 1e-9
        
        # 等待图像数据
        while rclpy.ok():
            if self.image is not None:
                return self.image
            
            # 检查是否超时
            current_time = self.get_clock().now().nanoseconds * 1e-9
            if current_time - start_time > timeout_sec:
                self.get_logger().warn(f'等待图像超时 ({timeout_sec}秒)')
                return None
            
            rclpy.spin_once(self, timeout_sec=0.1)
    
    def save_image(self, image, filename=None):
        """保存图像到文件"""
        if image is None:
            self.get_logger().error('错误：没有可用的图像')
            return
        
        if filename is None:
            # 默认文件名：当前时间戳
            filename = f'miro_camera_{datetime.now().strftime("%Y%m%d_%H%M%S")}.png'
        
        try:
            # 转换回BGR格式保存
            cv_image = cv2.cvtColor(image, cv2.COLOR_RGB2BGR)
            cv2.imwrite(filename, cv_image)
            self.get_logger().info(f'图像已保存为: {filename}')
        except Exception as e:
            self.get_logger().error(f'保存图像时出错: {e}')
    
    def show_image(self, image, title='Miro Camera Image'):
        """显示图像（使用matplotlib）"""
        if image is None:
            self.get_logger().error('错误：没有可用的图像')
            return
        
        plt.figure(figsize=(10, 8))
        plt.imshow(image)
        plt.title(title)
        plt.axis('off')
        plt.show()

# 使用示例
def main(args=None):
    rclpy.init(args=args)
    
    try:
        # 创建相机接口实例
        camera = MiroCameraROS2()
        
        # 循环获取并显示图像
        for i in range(5):  # 获取5次图像
            if not rclpy.ok():
                break
                
            # 获取最新图像
            image = camera.get_latest_image()
            
            # 显示并保存图像
            if image is not None:
                camera.show_image(image, f'Camera Image (Frame {i+1})')
                camera.save_image(image, f'camera_image_{i+1}.png')
    
    except KeyboardInterrupt:
        camera.get_logger().info('程序已被用户中断')
    finally:
        # 清理资源
        camera.destroy_node()
        rclpy.shutdown()

if __name__ == '__main__':
    main()    


#python3 camera.py --ros-args -p auto_detect:=true

# /apply_force ['cyberdog_msg/msg/ApplyForce']
# /clicked_point ['geometry_msgs/msg/PointStamped']
# /clock ['rosgraph_msgs/msg/Clock']
# /goal_pose ['geometry_msgs/msg/PoseStamped']
# /imu ['sensor_msgs/msg/Imu']
# /initialpose ['geometry_msgs/msg/PoseWithCovarianceStamped']
# /joint_states ['sensor_msgs/msg/JointState']
# /parameter_events ['rcl_interfaces/msg/ParameterEvent']
# /performance_metrics ['gazebo_msgs/msg/PerformanceMetrics']
# /rgb_camera/camera_info ['sensor_msgs/msg/CameraInfo']
# /rgb_camera/image_raw ['sensor_msgs/msg/Image']
# /robot_description ['std_msgs/msg/String']
# /rosout ['rcl_interfaces/msg/Log']
# /tf ['tf2_msgs/msg/TFMessage']
# /tf_static ['tf2_msgs/msg/TFMessage']
# /yaml_parameter ['cyberdog_msg/msg/YamlParam']