How to calibrate Stereo Camera?

Question

Hi, I am using Snapdragon_Dev_Board(eagle8074/Snapdragon801) with Stereo Camera. Snapdragon_Dev_Board has Linux Linaro 14.04(pre-loaded). I have installed ROS-Indigo on top of it. I am running two nodes snap_cam_ros https://github.com/ATLFlight/snap_cam_ros and dfs_ros_example https://github.com/ATLFlight/dfs-ros-example

to get the disparity image, depth image and point cloud.

While I am launching the snap_cam_ros on [Snapdragon_Dev_Board + Linux Linaro 14.04(pre-loaded) + ROS-Indigo] environment , using: roslaunch snap_cam_ros stereo.launch

it is showing the following error:

[ INFO] [7122.158294089]: using default calibration URL [ INFO] [7122.159528307]: camera calibration URL: file:///camera_info/left.yaml [ INFO] [7122.160654714]: Unable to open camera calibration file [/camera_info/left.yaml] [ WARN] [7122.161524713]: Camera calibration file /camera_info/left.yaml not found. [ INFO] [7122.162679974]: using default calibration URL [ INFO] [7122.163516068]: camera calibration URL: file:///camera_info/right.yaml [ INFO] [7122.164247578]: Unable to open camera calibration file [/camera_info/right.yaml] [ WARN] [7122.164905130]: Camera calibration file /camera_info/right.yaml not found. How to resolve this error: Can anyone help me out? Regards, Parwana Shahdi

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Originally posted by Parwana Shahdi on ROS Answers with karma: 11 on 2017-11-16

Post score: 0

Answer 1

Size of the checkerboard can be anything that you print out. As long as it is suitable enough to cover the entire stereo overlap region to get a good estimate of size but also provides enough samples along the x and y directions as well as skew samples. Print out whatever checkerboard works for you and then measure the square length and input that to your calibrator.

You can use the camera_calibration package which has a good tutorial

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Originally posted by 2ROS0 with karma: 1133 on 2017-11-16

This answer was ACCEPTED on the original site

Post score: 0

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Original comments

Comment by Parwana Shahdi on 2017-11-23:
Thanks; I did: 'roslaunch snap_cam_ros stereo.launch` I am finding the following error: using default calibration URL camera calibration URL: file:///camera_info/left.yaml Unable to open camera calibration file [/camera_info/left.yaml] Camera calibration file /camera_info/left.yaml not found.