This picture depicts a typical Cantonese mahjong game setup. The only things missing were the players and a square table.
In places where gambling is forbidden, colored chips are used to keep track of the winning and loss. The red chips are 50 unit each. The yellow chips are 10 unit each. The green chips are 1 unit each. Each player starts with 100 or 200 units. Players settle their winning at the end of the game by converting the chip to money. Some people who are defiant of the laws or don't worry about being caught by law enforcement may play with real money on the table instead of chips.
The green marker on the lower left is used for keeping track of the prevailing wind (it says East as shown), the dice in the marker can be flipped to show the other three wind directions. Three dice are used to determine the starting position of where to take the tiles at the beginning of each round. The holder of the marker is at EAST position. As it is shown here, the player at the near end is at the EAST position while the prevailing wind is also EAST. So if he managed to collect a pong of EAST in his winning hand, he receives two extra points. The other players are in the SOUTH, WEST, NORTH position respectively in the clockwise direction. They can win with one extra point if they manage to collect a pong of direction tiles to match the current position or the prevailing wind direction.
Each player holds 13 tiles until a gong is melded. Each gong will add one additional tile to the hand. The player who does a gong needs to draw a replacement tile from the tail end of the 'wall' of tiles.
In the picture, the player on the right has a gong of Fa exposed. The player on the left has a chow of bamboo tiles exposed. Both players at the far and near end have some flower tiles on the table. When a flower tile is drawn, it is exposed on the table and the player draw a replacement tile from the tail end of the 'wall' of tiles.
In this picture, the player on the near end holds a pong of the red dragon, a possible chow of 2-3-4 or 3-4-5 of circles if either the 2 or 5 is discarded. The 2-3-4-5 sequence can also be split into two melds when other tiles like 1 or 4 and 3 or 6 are drawn or chow'ed with the discarded tile from other player.