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Author Topic: Using exported camera parameters  (Read 5758 times)

tksharpless

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Using exported camera parameters
« on: February 02, 2024, 08:40:42 PM »
In my own software, I need to map 3D points to image coordinates using points and camera calibrations exported by MetaShape. To be sure I am doing this right, I would like to verify the mapping formulas that you use.  Is that information available? I am specifically interested in the frame and fish-eye camera models.

Alexey Pasumansky

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Re: Using exported camera parameters
« Reply #1 on: February 07, 2024, 04:16:11 PM »
Hello tksharpless,

The information about distortion models used in Metashape for frame and fisheye camera models is available in Appendix C of Metashape manual:
https://www.agisoft.com/pdf/metashape-pro_2_1_en.pdf

There were some examples on forum, how to get 2D coordinates of the 3D point on the image, so you can check the result you get externally with the "reference" values that you can get in Metashape directly using camera.project / camera.unproject methods and etc.
Best regards,
Alexey Pasumansky,
Agisoft LLC

tksharpless

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Re: Using exported camera parameters
« Reply #2 on: February 19, 2024, 02:18:47 AM »
Thanks, Alexey
I am testing those formulas from the appendix of the manual, using tie point data exported in BlocksExchange format and camera calibration data exported in Agisoft XML format. I am getting reasonable results with the frame camera model but not with the fisheye model.  It appears that the focal length in pixels exported for the fisheye model is too small -- only about 60% of the value I get from other calibration methods.  Am I misunderstanding something?
-- Tom