What topics gives me the output from the RGB camera respectively the depth sensor?

[JKjel1]

Hi,

I am very new to RealSense and ROS so my question could be bad formulated. I am using the RealSense D435 camera.

My goal is to read the streams from both the RGB camera and the depth sensor to use them independently with another program. I want to know the output from the separate streams so I know what input the other program should expect. 

I have downloaded the RealSense library and had a look at all the topics. My first thought was to use the /camera/color/image_raw topic to read from for the RGB stream and /camera/depth/image_rect_raw topic for the depth stream. But there are many more topics that are similar to the names so I am not sure. 

Is my understanding correct that I should use only two topics for my purpose or have I misunderstood the situation?

Any help is appreciated.

[MartyG]

My level of ROS knowledge is not advanced, so I may be of limited help with your question. I wanted to provide some kind of initial answer though.

I tried looking for an explanation for what each of the topics does but was unsuccessful. The next best thing may be to access the topics in the RViz program and adjust the settings to see how each one affects the camera view.

If you have already set up ROS, I would recommend visiting the guide in the link below and starting about halfway down the page at the 'running the cameras in ROS' heading to read how to play with the topics in RViz.

https://idorobotics.com/2018/11/02/integrating-the-intel-realsense-d435-with-ros/

[Alexandra_C_Intel]

Hi JKjel1, Thank you for your interest in the Intel RealSense D435 camera. You are correct. Those are the two topics you should use. You can follow the instructions on this page https://github.com/intel-ros/realsense, and use RViz to see the outputs from the topics. Regards, Alexandra

[JKjel1]

Okey good! I visualized it in RViz and it worked. But when I try to print the output in the terminal using rostopic echo /camera/color/image_raw I only see the numbers in a cluster (see picture) instead of numbers with representing titles.

Is there any way to get the number with titles? A command maybe? Or is it possible for me to create a new node which handles this?

[JKjel1]

I have fixed it now. the Data[] in sensor_msgs/Image parameter had an output so large that the terminal didn't allowed me to scroll to the top. All the titles were in the beginning of the printout.

[MartyG]

Glad you resolved your remaining issue. Thanks so much for the update!