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Author Topic: Reprojection Error  (Read 2047 times)

davidLi

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Reprojection Error
« on: July 11, 2019, 03:54:24 PM »
Dear All!

I very much would like to include the reprojection error in my Error Propagation.
As far as I understand it, this Error discribes the distance between a projected 3D-Point to a marked point in Pixels.
Now I would like to implement this value in my overall Error Propagation and get a value in a metric scale.

Here is what I'm thinking:
Can I simply muliplicate my reprojection Error with my Ground Resolution per Pixel to get a Reprojection error on a metric scale?

For Example:
I have a reprojection Error of 0,5 Pixels and a Ground resolution of 1,5 mm/Pixel
Would it be true to say that my Reprojection Error is actually 0,75 mm? 

Thank you for your help in advance!
David

Alexey Pasumansky

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Re: Reprojection Error
« Reply #1 on: July 11, 2019, 05:26:44 PM »
Hello David,

I think that more accurate way would be to calculate the distance between 3D point and a ray that goes through the camera center and corresponding pixel (point projection on the image).
Best regards,
Alexey Pasumansky,
Agisoft LLC

davidLi

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Re: Reprojection Error
« Reply #2 on: July 12, 2019, 10:13:06 AM »
Thank you for your reply Alexey!
I yet don't fully understand how I can operationalize your statement!
Could you maybe give an example on how such a calculation would look like?