A non-intrusive gesture recognition human-machine interaction system is proposed in this paper. In order to solve the hand positioning problem which is a difficulty in current algorithms, face detection is used for the pre-processing to narrow the search area and find user’s hand quickly and accurately. Hidden Markov Model (HMM) is used for gesture recognition. A certain number of basic gesture units are trained as HMM models. At the same time, an improved 8-direction feature vector is proposed and used to quantify characteristics in order to improve the detection accuracy. The proposed system can be applied in interaction equipments without special training for users, such as household interactive television
Current research on scannerless three dimensional imaging LiDAR mainly focus on the phase scannerless imaging
LiDAR, the multiple-slit streak tube imaging lidar and the flash LiDAR. But there are the disadvantages, such as short
detection range, the complicated structure of vacuum unit and lacking the grayscale images corresponding to the three
kinds of LiDAR listed above. In this paper we develop a novel 3D imaging LiDAR that works in the way of pushbroom. It
converts the time of flight (TOF) into the space with digital mirror device (DMD). When pulse arrives at the DMD, the
micromirrors are shifting from a status to another. Because the TOFs of pulses hit on different targets are different, there
will be the streak on the focal plane array (FPA) of the sensor, which shows the relative position. The relative position of
the streak can be used to reconstruct the range profile of the target. Compared with other three dimensional imaging
method, this new method has the advantages of high rate imaging, large field of view, simple structure and small size. First,
this article introduces the theory of digital micromirror laser 3D imaging LiDAR, and then it analyses the technical indicator
of the core component. At last, it gives the process of computing the detection range, theoretically demonstrating the
feasibility of this technology.
The raw data in binocular stereo image sequences is twice as that of monocular images, the large amount of information should be reduced. As a result there has been increasing attention given to image compression methods specialized to stereo pairs. Much of this work has concentrated on improving the disparity compensation process and codes the residual image similarly to a monocular image where one view is used to predict another, and the difference is coded. The residual image is usually composed primarily of strong vertical direction edge components surrounded by large areas of near zero intensity. The residual images have different characteristics, but they behave uniquely statistical regularity. This property is demonstrated experimentally in the paper. Two interested statistical variables are described, the one is the total number (N) of the pixels with near zero intensity in the residual image and other is the coordinate displacements (Δx, Δy) between the left and right image frames for get the residual image. Experimental results indicate that the curve between the parameters N and variables (Δx, Δy) may be fit by Gaussian function. The maximum of the variable Nm corresponding to the optimal displacements (Δxop, Δyop) may be estimated by the Gaussian approximation. An algorithm is further provided to quickly predict the minimal redundancy of the residual image and the corresponding displacement. It is shown how such characteristics may be of great benefit to quickly achieve the higher compression ratio.
In order to enhance the normal view angle of stereoscopic displays based on parallax illumination, the fundamental way is to restrict the width of the illuminating slit within narrow limits. But the knotty problem is that thin slit will dim the backlight and as a result dropping the brightness of display. A novel architecture to enable base liquid crystal displays to be higher brightness, lower cross talk and auto-stereoscopic mode is described in this paper. A high efficient parallax backlight comprising a recycle barrier block is placed at a distance behind an existing TFT-LCD panel. The barrier provides a series of bright illuminating slits for the parallax image pixels on the display panel and projects the alternate image columns to the observer. The slit is narrow in width so that the display may give diamond-shaped viewing regions with a width of 65mm with slightly cross talk. It can be seen that at the optimum viewing distance from the screen, stereoscopic image can be seen without any glasses. In this paper, the implementation of the backlight component in the auto-stereoscopic TFT-LCD is described in detail and the simulated data are given. The configuration of the prototype and measured performance are presented.