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by palata 1441 days ago
> A major reason for the quality issues is that the major drone manufacturers work directly with the proprietary photogrammetry software providers in the field to optimize the algorithms to their drones.

Would you care to elaborate? My belief is that all the photogrammetry engine wants is that the drone manufacturer does as few processing as possible on the images, in order to not alter the geometry. I don't see what kind of algorithms coming from the drone manufacturer would help, and therefore I don't see how that's a problem for ODM.
1 comments
pierotofy 1441 days ago
Direct knowledge of the lens distortion model and complete control of the image generation, with perfect knowledge and use of the associated metadata tags, can certainly give an engine a leg up in some cases. One example I can think of is the Parrot Sequoia which is a camera that works OK-ish in ODM, but works flawlessly with Pix4D (which is owned by Parrot).
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palata 1440 days ago
But none of that is private data, right? It feels like "tuning". Surely one could characterise Sequoia to improve the camera model, and I doubt they encrypt the exif data, do they? Also Sequoia is a bit of a special example here, that most likely has been carefully tuned by Pix4D. But DJI most probably does nothing for Pix4D that ODM couldn't access.

Not criticising ODM (I love OpenSfM and ODM), on the contrary: I feel like those are not fundamental limitations of ODM, and one could put the work of improving support for specific cameras without the need for proprietary information available only to Parrot employees.

Or am I missing something?

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pierotofy 1440 days ago
EXIF data is not encrypted, but often times is not documented (or documented well). DJI has many differences between models (even between firmware versions). They also sell DJI Terra, which is their own photogrammetry solution.

The point being that you are correct, these are not limitations of ODM, but in some cases it does give vendors a head start (a leg up) in implementing good support for certain cameras, especially multispectral cameras like the Sequoia.

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