The Study Of Key Algorithms Of Natural Human-computer Interaction Based On Hand

Vision-based human-computer interaction is a research focus in natural human-computer interaction field.It uses the visual information to capture from the video sequence, and makes the interaction between humans and computers out from the mouse and keyboard constraints. People can communicate with computer just through natural information such as body movements, gestures, and facial expressions.The exchange between humans and computers is more natural and smooth. Finger contains a large number of information in human-computer interaction process, so it is in a very important position in natural human-computer interaction system.Reference[31] indicate that finger interaction technology has four main applications:Sign language recognition;gesture recognition; Finger writing and virtual touch, how to get finger status information is one of the key points.It is possible to get finger status with the development of image processing,computer vision and artificial intelligence.However, due to hand is a multi-joint non-rigid object (Can be as high as27degrees of freedom [23]),so vision-based finger interaction is a challenging study. Domestic and foreign scholars and research institutions have made much effective research in the field of vision-based human-computer interaction systems.However, the majority of research has made harsh restrictions in application environment, and the environment is quite different with the real-world environments.So the vision-based human-computer interaction systems tend to only stay in the laboratory. According to this problem,this paper presented the complex environment skin detection algorithm,real-time fingertips localization algorithm and Tracking algorithm of random movement and high speed. Based on the above algorithms, we design and implement a vision-based human-computer interaction system. The contributions of this paper are as follows:1)Skin color detection in complex environments.According to the problem of poor color recognition in complex environment, this paper presented skin color detection based on color and part background subtraction algorithm.Firstly, the algorithm detects the skin color regions in background area with YCbCr color space.Secondly, it models the background in skin color regions with code book background modeling method.Thirdly, it initials detect skin color with static elliptical model in CbCr flat of YCbCr color space.If the initial detection skin color results have overlapping parts with skin color region in background, the algorithm uses part background subtraction to segment foreground skin color region in overlapping parts.The algorithm can effectively distinguish skin color and non-skin color in complex environment, and it possessed a very strong resilience and high efficiency2) Fingertip location.This paper presented fingertip location base on distance transform algorithm.Firstly, according to the problem that the3D hand models are too complex to real time calculate in vision-based human-computer interaction system, this paper presented a simplified2D hand model,and the characteristics of the model is emphasis on palm center of gravity position and fingertips position. Using this model,we can locate fingertips according to the distance between fingertips and palm of the center of gravity, if the palm center of gravity can be found accurately. Secondly, this paper presented palm of the center of gravity location algorithm based on distance transform.The palm of the center of gravity can be located accurately location by this algorithm.3)Fast moving target tracking.Tracking object which makes random and rapid movement is always a research focus.This paper presented a four-way prediction tracking algorithm based on particle filtering algorithm and Mean Shift algorithm. The algorithm combines respective advantages from both particle filtering algorithm and Mean Shift Algorithm.Firstly, it uses particle filtering algorithm to predict the possible region of target object. After that, we lock on the precise position of target object by using Mean Shift algorithm,which is proved to be efficient and speedy. Meanwhile, it uses the four-way prediction tracking algorithm to deal with the losing frames which lead by the random movement of target object, and makes a dramatically improvement for the possibility of tracking.Experimental results show the algorithm has high robust when tracking target with random and rapid movement.4) Tracking region initialization. Tracking regional initialization process is usually hand-finished in tracking method based on region. How to automatically initialize tracking regional has been a research difficulty. The algorithm can effectively use color detection and fingertip search results.5)Real-time hand motion tracking and fingertip location. The vision-based human-computer interaction system is a very complex, which related to a computer graphics, pattern recognition, artificial intelligence and many other fields.Therefore, how to effectively integrated differences algorithms is an important problem for any designer of human-computer interaction system. In this paper, the algorithms of complex environment skin color detection, part background subtraction, fingertip location and four-way prediction tracking are effective integration. We consider the reusability of the results of each algorithm;ensure the operational efficiency of the system.All of these formed the basis of human-computer interaction system. Experiments show that this system can be effectively used in vision-based human-computer interaction environment.