Image Acquisition, Processing And Display Implementation Of Infrared Imaging System

In recent years, infrared imaging technique develops rapidly. It is applied widely in the areas of night vision, navigation, scientific research and so on. But due to the influence of infrared detector and work environment, infrared imaging result is not so good with bad contrast. And its application effect is influenced in practical application. So it's necessary to make image enhancement on the acquired infrared image in order to improve the system imaging quality, and the processing image displayed on LCD for convenient and visual observation.In this paper, FPGA infrared image processing system is designed according to near-infrared CCD detector, including image acquisition, enhancement and LCD display module. The CCD timing driver is provided and the output CCD analog signal is processed by image acquisition module, finally required digital signal is gained. The infrared enhancement algorithm is a key step, and several infrared enhancement algorithms, such as gray transform and histogram equalization, are analyzed here. Comparing the algorithms by MATLAB simulation, auto-adaptive plateau histogram equalization algorithm is determined for infrared enhancement. Then FPGA system hardware and software are designed, using SOPC method to build hardware platform of image enhancement and Nios II program is programmed on this hardware platform, so infrared image enhancement is completed in FPGA. The core of LCD display module is LCD controller design. LCD timing driver and DMA function for reading data continuously are provided by it. Finally, it is packed as IP core and embedded in Nios II system in order to make LCD controlled by Nios II processor conveniently. Moreover, this controller can be configured, and the LCD resolution and FIFO memory size can be changed according to practical application, so it's very flexible.Infrared enhancement is made with adopted algorithm in FPGA and processing result is displayed on LCD. The display effect indicates that image quality is improved obviously with higher contrast and clearer fringe after auto-adaptive plateau histogram equalization enhancement. Therefore, infrared enhancement is realized in FPGA hardware platform. And LCD display of infrared enhanced image is also completed, making observation convenient and visual.