Detection of Fingertips in Human Hand Movement Sequences

This paper presents an hierarchical approach with neural networks to locate the positions of the fingertips in grey-scale images of human hands. The first chapters introduce and sum up the research done in this area. Afterwards, our hierarchical approach and the preprocessing of the grey-scale images are described. A low-dimensional encoding of the images is done by the means of Gabor-Filters and a special kind of artificial neural net, the LLM-net, is employed to find the positions of the fingertips. The capabilities of the system are demonstrated on three tasks: locating the tip of the forefinger and of the thumb, finding the pointing-direction regardless of the operator’s pointing style, and detecting all 5 fingertips in hand movement sequences. The system is able to perform these tasks even when the fingertips are in an area with low contrast.