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Author Topic: Align photos with markers only  (Read 6515 times)

j.seinturier

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Align photos with markers only
« on: June 05, 2015, 11:59:43 AM »
Hello,

I'm using Python scripting to make a camera calibration method using photoscan. This method is based on a calibration grid that contains 100 coded target that photoscan can detect as markers.

The algorithm is simple;

1. Detect markers on the photo
2. Affect local coordinates to markers (as i know exactly the grid geometry)
3. Align photographs
4. Optimize cameras.

This algorithm work fine if i make a point matching before aligning photographs (step 3.). If i do not make this matching, the photograph alignment is failing.

It seems that the markers cannot be used for photograph alignement.

My question is: Is it possible within photoscan to align a set of photographs by only using the detected markers ?

Thanks a lot,

Julien

Alexey Pasumansky

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Re: Align photos with markers only
« Reply #1 on: June 08, 2015, 07:53:33 PM »
Hello Julien,

You can try to match images with very low key point limit (1-10) before using alignCameras() function.
Best regards,
Alexey Pasumansky,
Agisoft LLC

j.seinturier

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Re: Align photos with markers only
« Reply #2 on: June 09, 2015, 10:31:30 AM »
Hi Alexey,

The solution does not work (no matchez are found and so not tie points are available). It seems that the markers are not integrated within the tie points. Is it possible to do this using python ? As i know the marker positions on each photograph and as i know the marker 3D coordinate, i should be able to "create" a tie point...

Seb_B

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Re: Align photos with markers only
« Reply #3 on: June 10, 2015, 01:28:51 PM »
Hello,

I am also interested to understand if Photoscan uses markers for the alignment step?

As I understand your answer Alexey, reducing the number of tie points will increase the wieght of the markers?

Sebastien