PokerStars windows don't even have to be visible, but cannot be minimalized. It needs admin privileges since it grabs screenshots with win32api. It's fastest way and do not require windows to be on top.
At the moment this app recons:
To make it work you need to set up orange table and default deck with 4 colors!
Letter "X" and "?" signs means that card wasn't recognized properly.
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Player cards: [T9, C6]
Cards on table: [TA, H6, H4, CJ, C5]
Game state: River
Table: Gotha VI
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Player cards: [T2, C6]
Cards on table: []
Game state: Prefloop
Table: Aida VI
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Player cards: []
Cards on table: [HQ, P8, C2]
Game state: Floop
Table: Aitne VI
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Each table has separate output and it's being send to stdout on change on this table.