Measurement
Homography
A homography is the mathematical mapping that converts the photographed slab face from image space into a flat metric plane.
What it means#
In slab capture, a homography maps points from the camera image to the real flat plane of the slab face. It is what lets a detected outline become a metric polygon instead of just pixels.
Why buyers care#
Without a valid homography, a remote listing should not claim millimetre dimensions. The measurement system needs a trustworthy scale reference on the slab face.
What to check#
Look for the precision badge, marker count, capture setup, and whether the listing reports a metric outline rather than only a photo.
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