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I was running pgr_camera_driver (with a PointGrey Flea3 GigE camera) that published both color image and camera_info with the same timestamp in tandam over wireless network. Color image and camera_info were subscribed by another program using image_transport::CameraSubscriber. I got error on synchronization between images and camera_info, and images were not received by the subscriber. The problem went away when the camera was connected through a wired connection. Does anyone experience the same problem? Any suggestion to make pgr_camera_driver work over wireless will be appreciated.

Thanks, CC


Originally posted by chyphen on ROS Answers with karma: 11 on 2013-07-30

Post score: 0


Original comments

Comment by TommyP on 2013-07-30:
What resolution and what frame rate? Use image_viewer to look at the image and make sure that you are not filling up the whole bandwidth. We have used an USB/Firewire PG Camera over WiFi and it works if we reduce the resolution or compress the image.

Comment by chyphen on 2013-07-30:
Resolution 640 by 480 at 15fps. Thanks for the suggestion.

CC

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It appears that this question describes a similar issue to the one you are having.

Have you considered/tried using message filters (more specifically, ApproximateTime) to synchronise the published colour image and published messages from the camera_info topic?

That worked for me, although I was synchronising 4 topics published by different sensors (also over a wireless connection).

Due to limited throughput and higher latency of wireless (as opposed to wired) connections, from my experience, messages are likely to get to the peer subscribing to such topics not necessarily at the same rate as they are published. Also, you might get a message from camera_info topic whilst the corresponding, synchronised sensor_msgs/Image is yet to be received by the subscriber.

I hope it helps!


Originally posted by Murilo F. M. with karma: 806 on 2013-07-30

This answer was ACCEPTED on the original site

Post score: 2

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