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1. 读取单个话题

1.1. 核心代码

   // 获取名为"my_topic"的话题的迭代器rosbag::View view(bag, rosbag::TopicQuery("my_topic"));

1.2. 完整示例

#include <ros/ros.h>
#include <rosbag/bag.h>
#include <std_msgs/String.h>int main(int argc, char** argv)
{// 初始化ROS节点ros::init(argc, argv, "play_bag_node");ros::NodeHandle nh;// 创建ROSbag对象，打开bag文件rosbag::Bag bag;bag.open("example.bag", rosbag::bagmode::Read);// 获取名为"my_topic"的话题的迭代器rosbag::View view(bag, rosbag::TopicQuery("my_topic"));// 循环遍历话题中的所有消息for (rosbag::View::iterator it = view.begin(); it != view.end(); ++it){// 转换消息类型std_msgs::String::ConstPtr msg = it->instantiate<std_msgs::String>();if (msg != NULL){// 打印消息内容ROS_INFO("Message: %s", msg->data.c_str());}}// 关闭bag文件bag.close();return 0;
}

2. 读取多个话题

2.1. 核心代码

 // 获取三个话题的迭代器rosbag::View view(bag, rosbag::TopicQuery("my_string_topic") && rosbag::TopicQuery("my_image_topic") && rosbag::TopicQuery("my_laser_topic"));

2.2. 完整示例

#include <ros/ros.h>
#include <rosbag/bag.h>
#include <std_msgs/String.h>
#include <sensor_msgs/Image.h>
#include <sensor_msgs/LaserScan.h>int main(int argc, char** argv)
{// 初始化ROS节点ros::init(argc, argv, "play_bag_node");ros::NodeHandle nh;// 创建ROSbag对象，打开bag文件rosbag::Bag bag;bag.open("example.bag", rosbag::bagmode::Read);// 获取三个话题的迭代器rosbag::View view(bag, rosbag::TopicQuery("my_string_topic") && rosbag::TopicQuery("my_image_topic") && rosbag::TopicQuery("my_laser_topic"));// 循环遍历话题中的所有消息for (rosbag::View::iterator it = view.begin(); it != view.end(); ++it){// 从bag文件中读取消息const rosbag::MessageInstance& msg = *it;// 根据消息类型进行强制转换if (msg.isType<std_msgs::String>()) {std_msgs::String::ConstPtr str_msg = msg.instantiate<std_msgs::String>();ROS_INFO_STREAM("String message: " << str_msg->data);}else if (msg.isType<sensor_msgs::Image>()) {sensor_msgs::Image::ConstPtr img_msg = msg.instantiate<sensor_msgs::Image>();ROS_INFO_STREAM("Image message: " << img_msg->header.stamp);// 在此处添加处理Image消息的代码}else if (msg.isType<sensor_msgs::LaserScan>()){sensor_msgs::LaserScan::ConstPtr scan_msg = msg.instantiate<sensor_msgs::LaserScan>();ROS_INFO_STREAM("LaserScan message: " << scan_msg->header.stamp);// 在此处添加处理LaserScan消息的代码}}// 关闭bag文件bag.close();return 0;}

3. 读取全部话题

3.1. 核心代码

rosbag::View view(bag);或者rosbag::View view(bag, rosbag::TopicQuery(bag.getTopics()));

3.2. 读取方式1

    rosbag::Bag bag;bag.open(bagpath, rosbag::BagMode::Read);if(!bag.isOpen()){cout<<"can't open bag file!"<<endl;      }rosbag::View view(bag);rosbag::View::iterator it = view.begin();int iIndexTopic = 0;for(;it!= view.end(); it++){if(it->getTopic() == "") continue;m[it->getTopic()] = 1;cout << "bag : " << it->getTopic() << it->getDataType() <<endl;}

3.3. 读取方式2

   int topic_num = view.getConnections().size();std::vector<std::string> tmp_topic;for (int i = 0; i < topic_num; i++){tmp_topic.push_back(view.getConnections().at(i)->topic);}

3.4. 完整示例

#include <rosbag/bag.h>
#include <rosbag/view.h>
#include <ros/ros.h>
#include <string>
#include <vector>
// 定义一个函数，用于回放多个话题的数据
// 参数：
// - bag_filename: ROSbag文件名
// - topics: 一个包含多个话题名的vector，如果为空，则回放所有话题的数据
void playbackRosbag(const std::string& bag_filename, const std::vector<std::string>& topics = {}){// 创建ROS节点// ros::NodeHandle nh("~");ros::NodeHandle nh;//sukai// 创建ROS话题发布器std::vector<ros::Publisher> pubs;for (const auto& topic : topics.empty() ? bag.getTopics() : topics){if (topic == "/image") {pubs.push_back(nh.advertise<sensor_msgs::Image>(topic, 1));}else if (topic == "/scan") {pubs.push_back(nh.advertise<sensor_msgs::LaserScan>(topic, 1));}else if (topic == "/string") {pubs.push_back(nh.advertise<std_msgs::String>(topic, 1));}else {ROS_WARN_STREAM("Unknown topic: " << topic);}}// 回放数据// rosbag::Bag bag(bag_filename, rosbag::bagmode::Read);rosbag::Bag bag;//sukaibag.open(bag_filename, rosbag::bagmode::Read); //sukairosbag::View view(bag, rosbag::TopicQuery(topics.empty() ? bag.getTopics() : topics));for (const auto& msg : view){ros::Time timestamp = msg.getTime();std::string topic = msg.getTopic();if (topic == "/image") {sensor_msgs::Image::ConstPtr image = msg.instantiate<sensor_msgs::Image>();if (image != nullptr) {pubs[0].publish(image);}}else if (topic == "/scan") {sensor_msgs::LaserScan::ConstPtr scan = msg.instantiate<sensor_msgs::LaserScan>();if (scan != nullptr) {pubs[1].publish(scan);}}else if (topic == "/string") {std_msgs::String::ConstPtr str = msg.instantiate<std_msgs::String>();if (str != nullptr) {pubs[2].publish(str);}}else {ROS_WARN_STREAM("Unknown topic: " << topic);}}// 关闭ROSbag文件bag.close();ROS_INFO_STREAM("Playback finished!");
}

主函数使用

int main(int argc, char** argv)
{ros::init(argc, argv, "rosbag_recorder_player");// 回放ROSbag文件中的所有话题数据playbackRosbag(bag_filename);// 回放ROSbag文件中的指定话题数据std::vectorstd::string playback_topics = {"/scan", "/string"};//playbackRosbag(bag_filename, playback_topics);playbackRosbag(bag_filename);return 0;
}