Integrated features and GMM Based Hand Detector Applied to Character Recognition System under Practical Conditions

Abstract

Detection of bare-hand under non-ideal conditions is a challenging task. Most of the existing hand detection systems are developed under limited environmental constraints. In this study, a robust two-level bare-hand detector is integrated with a 58 keyboard characters recognition model. At first, the Gaussian mixture model (GMM) based foreground detector is used to segment the region of interest (ROI), which is further classified using Color-texture and texture based models to detect the actual fist. The detected hand is tracked using modified Kanade–Lucas–Tomasi (KLT) tracker to generate the required trajectory points of the character. The feature space for character recognition consists of existing features and three new features, namely, Local Geometrical Area Ratio (LGAR), Area of two halves (ATH), Curve-Area feature (CAF) that are extracted from the trajectory points. Feature space is optimized using statistical analysis algorithms. Multi-factor analysis of individual character subsets such as alphabets, numbers, ASCII characters, etc., are carried out using multiple conventional classifiers along with Support vector machine (SVM), extreme learning machine (ELM), artificial neural network (ANN), and proposed Neuro-fuzzy classifiers. The proposed GMM based motion detection method achieves an accuracy of 100% during the segmentation of ROI, followed by an increase of 46.77% in the accuracy of two-level hand detection under non-ideal conditions. Maximum accuracy of 58 character system using proposed features and ANN classifier is observed to be 92.56%.