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camera_info topic is empty

asked 2018-04-25 04:39:28 -0600

Aviad gravatar image

Hi, I am using 2 usb cameras of logitech company to make a stereo mapping with my platform. I am using RTABmap for it. I made a driver for the cameras with uvc_camera package. The only topic that was published is the image_raw and the camera_info topic had no data. The matrix is all zeros. I searched in many sites and forums without any solution.

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answered 2018-04-25 10:47:54 -0600

bpinaya gravatar image

Did you calibrate the cameras? You should do that first so that you get some information about the cameras themselves. ROS by default doesn't know much about the camara you are plugin in. To start with the calibration run:

rosrun camera_calibration --size 8x6 --square 0.108 image:=/my_camera/image camera:=/my_camera

With the appropriate topics. You'll need a 8x6 chessboard with 108mm or the size you prefer, make sure to check the --size and --square parameters. An example chessboard panel is this one. Use it to calibrate the camaras and then you'll have some info about your cameras like distorsion and else.

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Hi, tnx you for your reply. Assume that I calibrated my cameras. How I can publish this information? I take calibrated data from the internet for my camera just to check this and after that I will do the specific calibration but now I can not publish that data to camera_info topic. please . tnx

Aviad gravatar image Aviad  ( 2018-04-25 10:55:50 -0600 )edit

Calibrating cameras is not hard at all, you could be done in 5 minutes or so. Once you get that done, the file will be saved into your ros directory and next time that'll be automatically published into camera_info topic :)

bpinaya gravatar image bpinaya  ( 2018-04-26 06:17:18 -0600 )edit

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Asked: 2018-04-25 04:39:28 -0600

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Last updated: Apr 25 '18