Calibration info for cameras

[niktnikt]

Hi,
Is it possible to provide camera calibration info to the simulator similar to what is here (http://docs.ros.org/en/melodic/api/sensor_msgs/html/msg/CameraInfo.html)? If yes, is it also possible to extract it?

[SijmenHuizenga]

Hi! At the moment CameraInfo is not being published. All transforms are available using the transform trees. If someone were to submit a pr adding CameraInfo publishing to the ros bridge I would be happy to review and merge it :)

[floriankittelmann]

Hi all,

This might be an old issue, but I am also quite interested in having a CameraInfo Topic for the depth camera. I need it because the current depth camera just outputs a Depth Image, but for my application I need a PointCloud with x,y,z coordinates. As I see from the documentation, there is already an existing package in ROS which is doing that (https://wiki.ros.org/depth_image_proc#depth_image_proc.2Fpoint_cloud_xyz), but it needs the CameraInfo Topic to get the correct x,y,z coordinates.

However, I am thinking about to add the CameraInfo Topic and make a PR. But I am not sure where or how I retrieve the correct information for the CameraInfo Topic. What are the informations for Intrinsic camera matrix (K), Rectification matrix (R), Projection/camera matrix (P), etc? These information seems for me to be sensor/camera specific and therefore I will need know how the camera/sensor gets simulated in the simulator..

Thanks in advance

[wouter-heerwegh]

Hi @floriankittelmann,

I don't have a clear idea of how to get this info yet, but I saw that this is implemented in [Airsim] (https://github.com/microsoft/AirSim/blob/master/ros/src/airsim_ros_pkgs/src/airsim_ros_wrapper.cpp) already. This might give some idea of how to get this info. It could be that our version does not support this yet as we are on Airsim 1.2 (I think).

[wouter-heerwegh]

I've seen that it is possible to pass through the FOV of the camera. This way we could calculate the intrinsics of the cameras (equations here can be used). For stereo camera's, the tf topics can be used.

As for depth cameras, I'm not sure yet. I would imagine it could be done in the same way but I would have to check