Details of Apple AAE sidecar files?

I know that AAE files are sidecars that describe the edits to photos made on an Apple product, and I've looked at the XML text itself.

I'm curious, though, if there's any information out there on what the XML consists of, i.e., how the code describes the edits?

It's clearly too short to be a bitmapped change. (I have Win10, iOS, and OSx hardware).

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