Requirements for the operation of the Visitors counter are given in the table:
Object images
Image quality: image must be clear, without obvious defects from the compression algorithm
Allowable person size: Person size is an area of the rectangle around a person as a percentage of the frame area. To correctly receive an event from the detector, you must select a person size in the range from the minimum value depending on the frame width up to 75% of the frame width.
Frame width isn't the original resolution of the video image, but the size of the frame based on the Frame size change parameter (see Configuring the Visitors counter).
The minimum size of a person, depending on the frame width, is given in the table: