1. A method for acquiring headcount, comprising: acquiring data frames from a surveillance video, setting object models in the data frames, and extracting a foreground image from the data frames, wherein the foreground image comprises moving objects extracted from the data frames; matching the moving objects in the foreground image with the object models, acquiring the headcount in corresponding data frames according to a result of the matching, extracting characteristics of the matched moving objects, and tracking the corresponding moving objects based on the characteristics; and acquiring the actual headcount for a predetermined time segment of the surveillance video based on a result of the tracking and the acquired headcount for each of the data frames, wherein the result of the tracking comprises: an indication of whether some or all of the data frames includes a same moving object or not.