An ideea hit me when I saw your post. I want to read an error code off a lcd display from a Viessmann Gas-fired wall-mounted condensing boiler.
For my water meter I use a Raspberry Pi and a Raspberry Pi Camera Module v2 and this app:
Seven Segment Optical Character Recognition
https://www.unix-ag.uni-kl.de/~auerswal/ssocr/index.html
