A computer implemented method for visual tracking of objects to be tracked over multiple frames of images photographed by a camera, the method comprising: selecting, from the objects to be tracked, non-high-priority objects and high-priority objects, wherein the high-priority objects are located right in front of an object tracking apparatus and move continuously and stably, such that a temporal variation over said multiple frames of a feature extracted for the objects to be tracked remains below a predetermined threshold; selecting, from the high-priority objects, high-priority objects whose movement coincides with movement of another high-priority object, as reliable high-priority objects; and tracking the reliable high-priority objects, wherein selecting the reliable high-priority objects includes determining first variability of variations of at least one first feature of a position, a velocity, a distance from the tracker's camera, and an occupation region in the image photographed by the camera of each high-priority object among a plurality of continuous frames; determining second variability of variations of at least one second feature of a relative distance, a relative angle, and a relative movement velocity between the high-priority object and another high-priority object; determining a confidence level based on at least one of the first variability and the second variability; and retaining the high-priority objects whose confidence level is greater than or equal to a predetermined threshold, as the reliable high-priority objects and converting a high-priority object into a non-high priority object if its confidence level is lower than the confidence level required for a high priority object, such that the high-priority objects are continuously updated as the tracking is performed, wherein the smaller the at least one of the first variability and the second variability is, the larger the confidence level is. selecting, from the objects to be tracked, non-high-priority objects and high-priority objects, wherein the high-priority objects are located right in front of an object tracking apparatus and move continuously and stably, such that a temporal variation over said multiple frames of a feature extracted for the objects to be tracked remains below a predetermined threshold; selecting, from the high-priority objects, high-priority objects whose movement coincides with movement of another high-priority object, as reliable high-priority objects; and tracking the reliable high-priority objects, wherein selecting the reliable high-priority objects includes determining first variability of variations of at least one first feature of a position, a velocity, a distance from the tracker's camera, and an occupation region in the image photographed by the camera of each high-priority object among a plurality of continuous frames; determining second variability of variations of at least one second feature of a relative distance, a relative angle, and a relative movement velocity between the high-priority object and another high-priority object; determining a confidence level based on at least one of the first variability and the second variability; and retaining the high-priority objects whose confidence level is greater than or equal to a predetermined threshold, as the reliable high-priority objects and converting a high-priority object into a non-high priority object if its confidence level is lower than the confidence level required for a high priority object, such that the high-priority objects are continuously updated as the tracking is performed, wherein the smaller the at least one of the first variability and the second variability is, the larger the confidence level is.