In this paper, we present a new method for counting people. This method is based on the head detection after a segmentation of the human body by skeleton graph process. The skeleton silhouette is computed and decomposed into a set of segments corresponding to the head, torso and limbs. This structure captures the minimal information about the skeleton shape. No assumption is made about the viewpoint, this is done after the head pose process. Several results present the efficiency of the labelling process , particularly its structural properties for the detection of heads within a crowd. A proposed method has been tested with an experiment of counting the number of pedestrians passing in a specific area.