Does not recognise a colon (e.g. in a 7 segment clock display)

[ThomasPDye]

Currently does not recognise colons in a 7 segment clock or stopwatch display.

[auerswal]

Yes, this functionality is currently missing. I do not know when I find the time to add it.

You might be able to work around this using, e.g., sed. Say a watch image saved as file image.png shows 12:34:56. ssocr would recognize this as 12134145. This could be post-processed to get the correct output as follows:

ssocr image.png | sed -E 's/([0-9]{2})1([0-9]{2})1([0-9]{2})/\1:\2:\3/'