A real time two-level method for fingertips tracking and number identification in a video

Abstract

This paper presents a real time method to estimate the number of fingers observed in a video. The method tracks the fingertips and exploits the shape of the hand contour to determine the number of fingers observed in a sequence of images. The first step of the proposed method is to detect the hand observed in the input image by segmentation into foreground and background areas using skin colour detection method. The foreground corresponds to the area representing the hand to be tracked. Due to the problem of the lighting variation, HSL colour space was used to represent the colour. The second step consists of computing the hand contour. Then a convex Hull and convexity defects are calculated to detect the fingertips. Principal components analysis (PCA) [13] method is applied on the convex hull to deal with the cases in which only one finger is observed in the image or when the hand is closed. The proposed method could be used to produce different Human Computer Interaction systems (HCI). Experimental results obtained from real images demonstrate the potential of the method.