People flow statistics method, device and system based on a visual sensor

The invention provides a people flow statistics method, device and system based on a visual sensor. The method comprises the steps of acquiring image data in a designated area according to a specificfrequency by utilizing the visual sensor; detecting all frames of images in the image data, and when it is identified that any frame of image comprises a portrait, allocating an identification numberfor the identified portrait; analyzing the effectiveness of the identification number on the basis of multiple frames of images continuous with any frame of image; and counting the identification numbers determined to be effective so as to realize statistics of people flow in the designated area. Based on the people flow statistics method provided by the invention, the analysis step is further added after the portrait is identified, so that the identification numbers can be further effectively analyzed; and the statistics of the people flow is realized by counting the effective identificationnumbers, so that the accura