Camera calibration

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thank you Mathieu.i have done the camera calibration on desktop,now i wanna reuse it on my phone. Do you have any idea how can i reuse the camera matrix and distortion coefficients?

The same way as in PC, with OpenCV functions (see remap in the doc). Maybe, if you don't want to support any other devices, you could directly hard code the values instead of loading an XML file.

I can't understand anything. can you please explain in more details. I generated an xml file to reused on my code. I'm looking to overlay a 3D model in a streaming from a live video.I'm working on android platforme.

On what part did you need more explanation ? If it was calibration, read carefully the tutorial (http://docs.opencv.org/doc/tutorials/calib3d/camera_calibration/camera_calibration.html) specially part 5 of Explanation section which relies on rectification of images. As said before (to the best of my knowledge) is should work either on PC and Android.

can you suggest a flow for calibrating android camera, through an android application. In certain application use cases, 1st time camera calibration is necessary. Thanks in advance !

The workflow is the same as in PC: 1) capture images of a chessboard 2) compute intrinsic parameters with findIntrinsic function 3) compute map of distortion, and remap original images. If you need extrinsic, after computing intrinsic, use findExtrinsic function.

But your solution will be very slow on Android, I've tested this solution on Samsung Note, and it's to slow to be really interesting. Maybe you should investigate a simpler calibration function, specially design for smartphone.

thanks Mathieu for sharing your experience regarding Android camera calibration. I am breaking my head on this problem since last few days, trying to write an Android application for Samsung Note, to calibrate its camera. The module is supposed to fit into an AR application, where distortion parameters of the camera are inevitable. Using the camera as webcam and then calibrating it, using a desktop application is a stopgap solution (since the developer like can do that), but for a crash free application development, need to look for better solutions. Also, different Android devices having different camera make, the distortion parameters might change. Many many thanks :)