A self-contained game monitoring device captures images of a game table and identifies objects relevant to the game and identifies values associated with objects. During the course of the game, the device can detect a violation of the players' bets according to pre-configured game rules. At the end of each game, the device can determine the outcome of the game (e.g., the win/lose/push on each bet) and can determine whether the dealer's action (e.g., payout on each bet) is consistent with the device's judgment. If an inconsistent action is detected, the device can notify the dealer/supervisor about a potential mistake.