Problem subscribing to image and camera_info about depthimage_to_laserscan HOT 5 CLOSED

First You need to tell the node where to find the depth image you want to transform. You can do this with

<remap from="image" to="your/topic"/>

in a launch-file. As it is already mentioned above.

After that I made a mistake: I didn't read the manual properly!

depthimage_to_laserscan uses lazy subscribing and will not subscribe to image or camera_info until there is a subscriber for scan.

When I was adding the output topic (default "/scan") to rviz the node (/depthimage_to_laserscan) was subscribing to my remapped depth image. Means the node is only subscribing to the image if some other node(s) are subscribing to its own output.

But I can't explain why You are seeing data in Your "/scan" topic. Maybe You have another node running publishing a "/scan" topic too?

from depthimage_to_laserscan.

Is there already a solution for this problem?

from depthimage_to_laserscan.

This is expected.

This node does lazy subscriptions so that it doesn't listen to the depth image topic to save bandwidth.

https://github.com/ros-perception/depthimage_to_laserscan/blob/indigo-devel/src/DepthImageToLaserScanROS.cpp#L46

https://github.com/ros-perception/depthimage_to_laserscan/blob/indigo-devel/src/DepthImageToLaserScanROS.cpp#L69-L84

from depthimage_to_laserscan.

@ctanzer Hey! Could you explain what you did so that it can be helpful for all of us? The ROS depthimage to laserscan page mentions that the subscribed topics are image and camera_info but when I look at the subscribed topic then I don't see any. However, I can see some data out of /scan. What is happening here?

Thank you for your help in advance!!

from depthimage_to_laserscan.

Hi @ctanzer Thank you for the explanation. There was only one /scan topic being published and that by the depthimage_to_laserscan node. I don't know why I was able to see the output of /scan topic even if nothing was subscribed to the same. However, I tried testing it with hector slam and it work perfectly. Thank you so much for your explanation. I have a question on ROS wiki regarding the same. If you would like to gain some points over there then simply copy paste the answer over there and I will accept it. However if not then I will simply update my question with your answer so that it might be helpful for someone having similar issue next time.

http://answers.ros.org/question/253473/depthimage_to_laserscan-not-subscribing-to-depth-by-kinect-360/

Thanks

from depthimage_to_laserscan.