5.1.5 使用ROS2 package

前提：已成功安装TogetheROS.Bot

tros.b和ROS2 Foxy/Humble版本接口完全兼容，能够复用ROS2丰富工具包，这里以安装和使用ROS2 image-transport为例介绍如何在tros.b中使用ROS package。

安装ROS2 package

1 添加ROS apt源

安装tros.b时，已自动添加ROS apt源，无需手动添加。

更新apt仓库

sudo apt update

注意

如果sudo apt update命令执行失败或报错，请查看常见问题章节的Q10: apt update 命令执行失败或报错如何处理？解决。

2 安装packages

Foxy

sudo apt install ros-foxy-image-transport
sudo apt install ros-foxy-image-transport-plugins

Humble

sudo apt install ros-humble-image-transport
sudo apt install ros-humble-image-transport-plugins

使用ROS2 package

与ROS使用一样

Foxy

source /opt/tros/setup.bash
ros2 run image_transport list_transports

Humble

source /opt/tros/humble/setup.bash
ros2 run image_transport list_transports

运行结果如下，展示了image_transport package支持的图像格式

root@ubuntu:/opt/tros# ros2 run image_transport list_transports
Declared transports:
image_transport/compressed
image_transport/compressedDepth
image_transport/raw
image_transport/theora

Details:
----------
"image_transport/compressed"
 - Provided by package: compressed_image_transport
 - Publisher:
      This plugin publishes a CompressedImage using either JPEG or PNG compression.

 - Subscriber:
      This plugin decompresses a CompressedImage topic.

----------
"image_transport/compressedDepth"
 - Provided by package: compressed_depth_image_transport
 - Publisher:
      This plugin publishes a compressed depth images using PNG compression.

 - Subscriber:
      This plugin decodes a compressed depth images.

----------
"image_transport/raw"
 - Provided by package: image_transport
 - Publisher:
      This is the default publisher. It publishes the Image as-is on the base topic.

 - Subscriber:
      This is the default pass-through subscriber for topics of type sensor_msgs/Image.

----------
"image_transport/theora"
 - Provided by package: theora_image_transport
 - Publisher:
      This plugin publishes a video packet stream encoded using Theora.

 - Subscriber:
      This plugin decodes a video packet stream encoded using Theora.