# 示例

您成功上传ROSBAG类型的场景文件至“场景管理”模块后，选择该场景文件进行仿真评测时，需要在相应的算法镜像中完成对rosbag处理的逻辑和评测目标数据向protobuf的类型转换，才可进行评测。本节提供一份示例，您可参考示例逻辑进行处理。示例只提供一种处理思路，最终评测需要的是一份符合protobuf messasge规范的数据文件，您可自行决定如何处理。

# 算法镜像

  FROM *********    #基础镜像
  # 创建一个使用 roslaunch 文件的 rospkg, 方便处理 rosbag 的 play 和 record
  RUN mkdir -p /opt/record_ws/src \
  WORKDIR /opt/record_ws/src
  RUN /bin/bash -c "source /ros_entrypoint.sh" \
  && catkin_create_pkg record_pkg std_msgs rospy roscpp \
  && cd ../ \
  && /bin/bash -c '. /opt/ros/melodic/setup.bash; cd /opt/record_ws;
  catkin_make' \
  && echo "source /opt/record_ws/devel/setup.bash" >> ~/.bashrc \
  && /bin/bash -c "source /opt/record_ws/devel/setup.bash" \
  && mkdir /opt/record_ws/src/record_pkg/launch
  WORKDIR /opt/record_ws/src/record_pkg/launch
  ADD record.launch ./
  # 将用于将 record的rosbag数据 转换为 pb文件的操作文件置于合适位置（取决于用户逻辑）
  WORKDIR /opt/bag_to_proto/
  ADD bag_to_proto /opt/bag_to_proto/
  RUN pip3 install -r requirements.txt
  # resim.sh 文件用于管理启动命令
  WORKDIR /
  ADD resim.sh /
  RUN chmod +x /resim.sh

示例镜像构建过程可能涉及到的文件：

record.launch

 <launch>
 <node pkg="rosbag" type="play" name="player" output="screen"
 args="/opt/rosbag/bag/bagname
 /planning/planning_info:=/planning/planning_info_1
 /planning/trajectory:=/planning/trajectory_1
 /planning/trajectory_viz:=/planning/trajectory_viz_1
 /localization_info:=/localization_info_1" required = "true"/>
 <node pkg="rosbag" type="record" name="bag_record"
 args="/localization_info -O /opt/rosbag/bag/new_evaluate.bag"/>
 </launch>

pb转换

evaluation_input.proto 定义规范msg的文件；
使用_protoc compiler_ 将proto文件生成为对应语言的解释msg的文件，示例生成使用的为
```
proto/evaluation_input_pb2.py
```

转换过程

 #!/usr/bin/env python
 import os
 import time
 import math
 from bagpy import bagreader
 import pandas as pd
 from proto.evaluation_input_pb2 import EgoStateResult
 from proto.evaluation_input_pb2 import EgoStateFrame
 start_time, sim_time, simulation_frequency = (0, 0, 0)
 def parse_rosbag(bag_path: str):
 b = bagreader(bag_path)
 msg_localization = b.message_by_topic('/localization_info')
 pandas_localization = pd.read_csv(msg_localization)
 # create pb object of ego_state
 ego_state_object = EgoStateResult()
 handle_localization(pandas_localization, ego_state_object)
 ego_state_data = ego_state_object.SerializeToString()
 # dump pb bytes data to a file
 with open("/opt/rosbag/bag/ego_state.pb", "wb") as fb:
 fb.write(ego_state_data)
 def handle_localization(pandas_localization, ego_state_object):
 secs_time = pandas_localization['header.stamp.secs']
 nsecs_time = pandas_localization['header.stamp.nsecs']
 total_frame = len(secs_time)
 for frame_num in range(total_frame):
 handle_timestamp(frame_num, secs_time[frame_num],
 nsecs_time[frame_num])
 convert_localization_to_pb_ego_state(pandas_localization,
 ego_state_object, frame_num)
 def handle_timestamp(frame_num, secs_time, nsecs_time):
 global start_time, sim_time, simulation_frequency
 secs = secs_time
 nsecs = nsecs_time
 if frame_num == 0:
 start_time = secs + nsecs / 10 ** 9
 sim_time = 0
 elif frame_num == 1:
 period = secs + nsecs - start_time
 simulation_frequency = int(1 / period)
 sim_time = secs + nsecs / 10 ** 9 - start_time
 else:
 sim_time = secs + nsecs / 10 ** 9 - start_time
 def convert_localization_to_pb_ego_state(pandas_localization,
 ego_state_object, frame_num):
 ego_state_frame = EgoStateFrame()
 ego_state_frame.sim_time = sim_time
 ego_state_frame.ego_state.id = 1
 ego_state_frame.ego_state.type = 1
 ego_state_frame.ego_state.geo.dimX = 4.866
 ego_state_frame.ego_state.geo.dimY = 1.832
 ego_state_frame.ego_state.geo.dimZ = 1.464
 ego_state_frame.ego_state.geo.offX = 4.866
 ego_state_frame.ego_state.geo.offY = 1.832
 ego_state_frame.ego_state.geo.offZ = 1.464
 ego_state_frame.ego_state.pos.x =
 pandas_localization['pose.position.x'][frame_num]
 ego_state_frame.ego_state.pos.y =
 pandas_localization['pose.position.y'][frame_num]
 ego_state_frame.ego_state.pos.z =
 pandas_localization['pose.position.z'][frame_num]
 orientation_x = pandas_localization['pose.orientation.x'][frame_num]
 orientation_y = pandas_localization['pose.orientation.y'][frame_num]
 orientation_z = pandas_localization['pose.orientation.z'][frame_num]
 orientation_w = pandas_localization['pose.orientation.w'][frame_num]
 roll_angle, pitch_angle, yaw_angle = to_euler_angles(orientation_w,
 orientation_x, orientation_y, orientation_z)
 ego_state_frame.ego_state.pos.h = yaw_angle
 ego_state_frame.ego_state.pos.p = pitch_angle
 ego_state_frame.ego_state.pos.r = roll_angle
 ego_state_frame.ego_state.speed.x =
 pandas_localization['velocity.linear.x'][frame_num]
 ego_state_frame.ego_state.speed.y =
 pandas_localization['velocity.linear.y'][frame_num]
 ego_state_frame.ego_state.speed.z =
 pandas_localization['velocity.linear.z'][frame_num]
 ego_state_frame.ego_state.speed.h =
 pandas_localization['velocity.angular.z'][frame_num]
 ego_state_frame.ego_state.speed.p =
 pandas_localization['velocity.angular.y'][frame_num]
 ego_state_frame.ego_state.speed.r =
 pandas_localization['velocity.angular.x'][frame_num]
 ego_state_frame.ego_state.acceleration.x =
 pandas_localization['acceleration.linear.x'][frame_num]
 ego_state_frame.ego_state.acceleration.y =
 pandas_localization['acceleration.linear.y'][frame_num]
 ego_state_frame.ego_state.acceleration.z =
 pandas_localization['acceleration.linear.z'][frame_num]
 ego_state_frame.ego_state.acceleration.h =
 pandas_localization['acceleration.linear.z'][frame_num]
 ego_state_frame.ego_state.acceleration.p =
 pandas_localization['acceleration.linear.y'][frame_num]
 ego_state_frame.ego_state.acceleration.r =
 pandas_localization['acceleration.linear.x'][frame_num]
 ego_state_object.ego_state_frame.extend([ego_state_frame])
 def to_euler_angles(w, x, y, z):
 """w、x、y、z to euler angles"""
 roll = math.atan2(2 * (w * x + y * z), 1 - 2 * (x * x + y * y))
 pitch = math.asin(2 * (w * y - z * x))
 yaw = math.atan2(2 * (w * z + x * y), 1 - 2 * (z * z + y * y))
 angles = (roll, pitch, yaw)
 return angles
 if __name__ == "__main__":
 bag_file_path = "/opt/rosbag/bag/new_evaluate.bag"
 while True:
 time.sleep(1)
 print("waiting for bag file")
 if os.path.exists(bag_file_path):
 break
 parse_rosbag(bag_file_path)

resim.sh

#!/bin/bash
# 处理资源，并确定资源路径
BAG_NAME=${BAG_FILE_NAME} # /opt/rosbag/bag/xxx.bag
XODR_PATH=${OPENDRIVE_PATH} # /opt/rosbag/xodr/xxx.xodr
source /ros_entrypoint.sh
source /root/demo/devel/setup.bash
roscore &
# 启动算法模块
rosrun planner demo_planning_node &
rosrun controller demo_controller_node &
# 预留30s 保证算法模块启动完成
sleep 30
# 处理rosbag play & record 中的资源名称
source /opt/record_ws/devel/setup.bash
sed -i "s/bagname/${BAG_NAME}/g"
/opt/record_ws/src/record_pkg/launch/record.launch
roslaunch record_pkg record.launch &
# 用于将新 record 的 /opt/rosbag/bag/new_evaluate.bag 转换为pb文件
python3 /opt/bag_to_proto/rosbag_to_pb.py

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