Real Time Static Gesture Recognition Using Time of Flight Camera: Scientific Approach

Hand gesture recognition is challenging task in machine vision due to similarity between inter class
samples and high amount of variation in intra class samples. The gesture recognition independent of
light intensity, independent of color has drawn some attention due to its requirement where system
should perform during night time also. This paper provides an insight into dynamic hand gesture
recognition using depth data and images collected from time of flight camera. It provides user
interface to track down natural gestures. The area of interest and hand area is first segmented out
using adaptive thresholding and region labeling. It is assumed that hand is the closet object to
camera. A novel algorithm is proposed to segment the hand region only. The noise due to ToF
camera measurement is eliminated by preprocessing algorithms. There are two algorithms which we
have proposed for extracting the hand gestures features. The first algorithm is based on computing
the region distance between the fingers and second one is about computing the shape descriptor of
gesture boundary in radial fashion from the centroid of hand gestures. For matching the gesture the
distance between two independent regions is computed for every row and column. Same process is
repeated across the columns. The number of total region transitions are computed for every row and
column. This number of transitions across rows and columns forms the feature vector. The proposed
solution is easily able to deal with static and dynamic gestures. In case of second approach we
compute the distance between the gesture centroid and shape boundaries at various angles from 0 to
360 degrees. These distances forms the feature vector. Comparison of result shows that this method
is very effective in extracting the shape features and competent enough in terms of accuracy and
speed. The gesture recognition algorithm mentioned in this paper can be used in automotive
infotainment systems, consumer electronics where hardware needs to be cost effective and the
response of the system should be fast enough.