Design And Implementation Of The Human-computer Interaction Laser Pen Based On Image Processing

The laser pen has a wide range of applications in multimedia content demonstration area such as CAI, the speaker indicates the multimedia content via the laser points on the projection screen and then guide the audience’s attention. With the continuous iteration of the product, the user still needs to be done on the computer keyboard operation in most cases, although the laser pen on the current market has the basic functions, such as PPT paging up and down, which affects the efficiency of teaching or speech and also makes the user still needs to be done on the computer keyboard operation. It makes the user can’t put more effort on the interaction with the audience and leads to lower quality of teaching or speech. In this paper, we implement an embedded laser pointer device which is designed to strengthen man-machine remote interaction. The device can collect images through a video camera and move the mouse pointer to the position of the laser point and complete some keyboard keystrokes when the user press down the button of the laser pen.This paper is based on the human-computer interaction laser pen project and first expounds the research background and introduces the current status of the development of related products on the market and then makes a detailed analysis of the functional requirements of the overall system and each function module. This paper introduces the overall design of the system scheme and involved key technologies and expounds emphatically the development of the hardware driver of the embedded laser pen and the video image processing software on PC. In the concrete implementation of the system, it divides into two parts, hardware driver and PC software, including driven development of the camera module and WIFI module which are based on the STM32 processor platform, image data receiving, the detection and location of the laser spot and computer screen, the key control etc. The embedded laser pen consists of the camera module and wireless communication module. It can laser emission wavelength in the visible range and also send the images collected by the video camera to PC. The PC software deals with the image data. It determines the laser spot positioning coordinates through the position of the computer screen in the images and monitor the user’s key commands at the same time to control the mouse pointer with laser spot and complete the relevant key function.Finally the paper completes the system function test and expounds the test results and put forward feasible suggestions for further research and development. Actual test can indicate that the system realizes the collection and transmission of image data and also the location of the laser spot and the screen and relevant key operation. The system meets the requirements of the function of the multimedia presentation and gets good user experience.