Weighing system, weighing device, and weighing method

A transaction processing system for weighed commodities, the transaction processing system comprising:

• a server device;
• and
• a weighing device including:
• a display screen
• a weighing unit configured to detect a change in weight of items in a container on the weighing unit, wherein
• when the weighing unit detects a reduction in the weight of items in the container, the weighing device generates an encoded image encoding a weight change value corresponding to the reduction in weight and a weighing device code identifying the weighing unit, and displays the encoded image on the display screen.

A weighing device for transaction processing systems, the weighing device comprising:

• a communication unit connectable to a server device;
• and
• a weighing unit configured to detect a change in weight of items in a container on the weighing unit, wherein
• when the weighing unit detects a reduction in the weight of items in the container, the weighing device transmits a weight change notice to the server device via the communication unit, the weight change notice including a weight change value corresponding to the reduction in weight and a weighing device code identifying the weighing unit.