protocol 测试

脑洞大开一下，想比较一下rosbag和protocol谁的存储性能好一些。最后的结果是protocol小胜。

实验环境是在ros下，有一个实验用的bag，其中有发布scan。 分别用rosbag和自己写的ros节点，使用proto转存激光雷达的数据。

最后rosbag记录下的文件是157.9M  proto是154.0M。

下面是工程代码

#include "ros/ros.h"
#include "std_msgs/Header.h"
#include "sensor_msgs/LaserScan.h"
#include <iostream>
#include <fstream>
#include <string>
#include "laser.pb.h"
using namespace std;

LaserScanBag laser_scan_bag;

void chatterCallback(const sensor_msgs::LaserScan& scan)
{
//ROS_INFO("I heard: [%s]", msg->data.c_str());
cout << scan.header.stamp.sec << " " << scan.header.stamp.nsec << endl;
LaserScan *laser_scan_ptr = laser_scan_bag.add_laserscan();

laser_scan_ptr->set_angle_min(scan.angle_min);
laser_scan_ptr->set_angle_max(scan.angle_max);
laser_scan_ptr->set_angle_increment(scan.angle_increment);
laser_scan_ptr->set_time_increment(scan.time_increment);
laser_scan_ptr->set_scan_time(scan.scan_time);
laser_scan_ptr->set_range_min(scan.range_min);
laser_scan_ptr->set_range_max(scan.range_max);
for(int i=0;i<scan.ranges.size();i++)
laser_scan_ptr->add_range(scan.ranges[i]);

}

int main(int argc, char **argv)
{
GOOGLE_PROTOBUF_VERIFY_VERSION;

ros::init(argc, argv, "listener");
ros::NodeHandle n;
ros::Subscriber sub = n.subscribe("scan", 1000, chatterCallback);

fstream input("laser_bag", ios::in | ios::binary);
if(!input)
{
cout << "create laser_bag" << endl;
}
else if(!laser_scan_bag.ParseFromIstream(&input))
{
cerr << "fail to open laser_bag!";
return 1;
}

while(ros::ok())
{
ros::spinOnce();
}
cout << "start write file" << endl;
fstream output("laser_bag", ios::out | ios::trunc | ios::binary);
if (!laser_scan_bag.SerializeToOstream(&output)) {
cerr << "Failed to write address book." << endl;
return -1;
}

cout << "end write file" << endl;

cout << "end program" << endl;

google::protobuf::ShutdownProtobufLibrary();

return 0;
}



这是cmakelists，重点是最后几句话

cmake_minimum_required(VERSION 2.8.3)
project(proto_test)

## Find catkin macros and libraries
## if COMPONENTS list like find_package(catkin REQUIRED COMPONENTS xyz)
## is used, also find other catkin packages
find_package(catkin REQUIRED COMPONENTS
roscpp
sensor_msgs
std_msgs
)

## System dependencies are found with CMake's conventions
# find_package(Boost REQUIRED COMPONENTS system)

## Uncomment this if the package has a setup.py. This macro ensures
## modules and global scripts declared therein get installed
## See http://ros.org/doc/api/catkin/html/user_guide/setup_dot_py.html # catkin_python_setup()

################################################
## Declare ROS messages, services and actions ##
################################################

## To declare and build messages, services or actions from within this
## package, follow these steps:
## * Let MSG_DEP_SET be the set of packages whose message types you use in
## your messages/services/actions (e.g. std_msgs, actionlib_msgs, ...).
## * In the file package.xml:
## * add a build_depend tag for "message_generation"
## * add a build_depend and a run_depend tag for each package in MSG_DEP_SET
## * If MSG_DEP_SET isn't empty the following dependency has been pulled in
## but can be declared for certainty nonetheless:
## * add a run_depend tag for "message_runtime"
## * In this file (CMakeLists.txt):
## * add "message_generation" and every package in MSG_DEP_SET to
## find_package(catkin REQUIRED COMPONENTS ...)
## * add "message_runtime" and every package in MSG_DEP_SET to
## catkin_package(CATKIN_DEPENDS ...)
## * uncomment the add_*_files sections below as needed
## and list every .msg/.srv/.action file to be processed
## * uncomment the generate_messages entry below
## * add every package in MSG_DEP_SET to generate_messages(DEPENDENCIES ...)

## Generate messages in the 'msg' folder
# add_message_files(
# FILES
# Message1.msg
# Message2.msg
# )

## Generate services in the 'srv' folder
# add_service_files(
# FILES
# Service1.srv
# Service2.srv
# )

## Generate actions in the 'action' folder
# add_action_files(
# FILES
# Action1.action
# Action2.action
# )

## Generate added messages and services with any dependencies listed here
# generate_messages(
# DEPENDENCIES
# sensor_msgs# std_msgs
# )

################################################
## Declare ROS dynamic reconfigure parameters ##
################################################

## To declare and build dynamic reconfigure parameters within this
## package, follow these steps:
## * In the file package.xml:
## * add a build_depend and a run_depend tag for "dynamic_reconfigure"
## * In this file (CMakeLists.txt):
## * add "dynamic_reconfigure" to
## find_package(catkin REQUIRED COMPONENTS ...)
## * uncomment the "generate_dynamic_reconfigure_options" section below
## and list every .cfg file to be processed

## Generate dynamic reconfigure parameters in the 'cfg' folder
# generate_dynamic_reconfigure_options(
# cfg/DynReconf1.cfg
# cfg/DynReconf2.cfg
# )

###################################
## catkin specific configuration ##
###################################
## The catkin_package macro generates cmake config files for your package
## Declare things to be passed to dependent projects
## INCLUDE_DIRS: uncomment this if you package contains header files
## LIBRARIES: libraries you create in this project that dependent projects also need
## CATKIN_DEPENDS: catkin_packages dependent projects also need
## DEPENDS: system dependencies of this project that dependent projects also need
catkin_package(
# INCLUDE_DIRS include
# LIBRARIES proto_test
# CATKIN_DEPENDS protobuf roscpp sensor_msgs std_msgs
# DEPENDS system_lib
)

###########
## Build ##
###########

## Specify additional locations of header files
## Your package locations should be listed before other locations
# include_directories(include)
include_directories(
${catkin_INCLUDE_DIRS}
)

## Declare a C++ library
# add_library(proto_test
# src/${PROJECT_NAME}/proto_test.cpp
# )

## Add cmake target dependencies of the library
## as an example, code may need to be generated before libraries
## either from message generation or dynamic reconfigure
# add_dependencies(proto_test ${${PROJECT_NAME}_EXPORTED_TARGETS} ${catkin_EXPORTED_TARGETS})

## Declare a C++ executable
# add_executable(proto_test_node src/proto_test_node.cpp)

## Add cmake target dependencies of the executable
## same as for the library above
# add_dependencies(proto_test_node ${${PROJECT_NAME}_EXPORTED_TARGETS} ${catkin_EXPORTED_TARGETS})

## Specify libraries to link a library or executable target against
# target_link_libraries(proto_test_node
# ${catkin_LIBRARIES}
# )

#############
## Install ##
#############

# all install targets should use catkin DESTINATION variables
# See http://ros.org/doc/api/catkin/html/adv_user_guide/variables.html
## Mark executable scripts (Python etc.) for installation
## in contrast to setup.py, you can choose the destination
# install(PROGRAMS
# scripts/my_python_script
# DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
# )

## Mark executables and/or libraries for installation
# install(TARGETS proto_test proto_test_node
# ARCHIVE DESTINATION ${CATKIN_PACKAGE_LIB_DESTINATION}
# LIBRARY DESTINATION ${CATKIN_PACKAGE_LIB_DESTINATION}
# RUNTIME DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
# )

## Mark cpp header files for installation
# install(DIRECTORY include/${PROJECT_NAME}/
# DESTINATION ${CATKIN_PACKAGE_INCLUDE_DESTINATION}
# FILES_MATCHING PATTERN "*.h"rosrun
# PATTERN ".svn" EXCLUDE
# )

## Mark other files for installation (e.g. launch and bag files, etc.)
# install(FILES
# # myfile1
# # myfile2
# DESTINATION ${CATKIN_PACKAGE_SHARE_DESTINATION}
# )

#############
## Testing ##
#############

## Add gtest based cpp test target and link libraries
# catkin_add_gtest(${PROJECT_NAME}-test test/test_proto_test.cpp)
# if(TARGET ${PROJECT_NAME}-test)
# target_link_libraries(${PROJECT_NAME}-test ${PROJECT_NAME})
# endif()

## Add folders to be run by python nosetests
# catkin_add_nosetests(test)
LINK_DIRECTORIES(/usr/lib/x86_64-linux-gnu)

add_executable(test_main src/test_main.cpp src/laser.pb.cc)
target_link_libraries(test_main ${catkin_LIBRARIES} -lprotobuf )

最后是.proto。稍稍修改了一下googl里的数据格式，为了和rosbag记录下的相同（但是还是少记录了一个header，所以有点不严谨，但是相比于每一帧激光的数据，header有和没有差不多）
message LaserScan {

optional float angle_min = 2;
optional float angle_max = 3;
optional float angle_increment = 4;
optional float time_increment = 5;
optional float scan_time = 6;
optional float range_min = 7;
optional float range_max = 8;

repeated float range = 9 [packed = true];
repeated float intensity = 10 [packed = true];
}

message LaserScanBag{
repeated LaserScan laserscan = 1;
}