System, method and storage medium for detecting people entering and leaving a field

A system for detecting people entering and leaving a field, comprising:

• a camera, disposed at a high place, capturing an entrance from a depression angle and outputting an image stream at the same time;
• and
• a processor, coupled to the camera, configured to receive the image stream and set an event detection area corresponding to the entrance, wherein the event detection area comprises an upper boundary, a lower boundary, and an internal area, and the lower boundary comprises a left boundary, a right boundary, and a bottom boundary,
• wherein the processor is configured to detect and track a person image corresponding to a person in the image stream, and the person image is a whole-body image or a partial image,
• wherein the processor is configured to determine whether the person passes through or does not pass through the entrance according to a first detection result and a second detection result,
• wherein when the first detection result indicates that a coordinate position where a candidate area corresponding to the person image first appears is located in the internal area, and the second detection result indicates that the candidate area passes through the lower boundary and leaves the event detection area, the processor determines that the person passes through the entrance,
• wherein when the first detection result indicates that the candidate area moves from outside the event detection area, passes through the lower boundary, and enters the internal area, and the second detection result indicates that a coordinate position where the candidate area disappears is located in the internal area, the processor determines that the person passes through the entrance.