What is the definition of "scene center"?

[DFEvans]

Certain view angles are described as being defined from "the scene center point". However, a definition of that point is not given - what was in mind when it was written? Is there a standard industry definition?

I can think of a few different interpretations:

• The projected location of the central pixel in the camera array for frame imagers, or the "central" pixel in a scan. I'm unsure if this concept makes sense for all possible datasets the extension covers (SAR in particular).
• The centroid of all pixels containing data (is the centroid derived in sensor space and projected, or from the pixels after projection?)
• The centroid of the bounding box or bounding polygon
• Something else!

Admittedly, if one cares enough to ask, then per-pixel metadata is probably needed, but it'd be good to pin down the definition.

[matthewhanson]

Hello @DFEvans, good call, 'target' is ambiguous.

I think that that scene center is the centroid of the Item geometry (which is the Polygon or MultiPolygon of where all the data is).

This might not match exactly any particular vendor, if they calculate their average angles using another method but at least this is providing some more specific guidance.