On Tue, Apr 6, 2010 at 4:24 PM, Adam Leeper <aleeper@stanford.edu> wrote:

> On a related note, what is the proper way to publish camera info? Do I
> write a node that just publishes the message every few seconds? It seems
> that the camera info doesn't change quickly :)
>

You need to publish one camera info message for every image message, and
they should have the same timestamp.
image_transport::CameraPublisher<http://www.ros.org/doc/api/image_transport/html/classimage__transport_1_1CameraPublisher.html>is
a convenience class that exists mainly to make the (image, camera
info)
pairing explicit.

It's true the camera info doesn't change quickly, but only because no one
(AFAIK) is doing continuous calibration in ROS yet :). Also, drivers can
allow changing parameters like region of interest dynamically, which affects
how you interpret the calibration parameters.

Patrick