The Research On High-resolution Digital Camera

With the development of digital image processing technology, image quality requirements have become more sophisticated. The digital camera as an important tool of image acquisition is moving to high frame rate, high resolution, high-speed, high-quality direction. The key technology of the image quality is the automatic white balance, auto exposure, auto focus. Good automatic white balance algorithms, auto exposure algorithms and precise auto-focus algorithm are the premise of high-quality images obtained. Paper finds that the traditional algorithms which are for data processing hardware for high speed and difficult in hardware-based, does not apply to digital imaging equipment. In view of these adverse factors, this paper proposes the auto exposure, auto white balance, auto focus algorithm based digital image.In the High-resolution digital camera system, this paper firstly discusses the overall system architecture, then introduces the system of image sensor module, the image pre-processing module, video data conversion module, the data cache module, power module, HDMI(High Definition Multimedia Interface) signal generation module and the system control module and other modules. The cores of hardware design of system are CPLD(Complex Programmable Logic Device), dedicated video conversion chip WSC2810and MCU. The algorithms are own automatic white balance algorithms, auto exposure and auto focus algorithm. CPLD is responsible for the implementation of algorithms. Firstly, it extracts the high frequency components of image clarity, brightness histogram and representative image of the white point of the pixel; then determines the location of accumulation, exposure situation, statistics pixel RGB white point average, calculates the RGB Gain adjusted; Finally, MCU controls position of stepper motor rotation, exposure time and writes the corresponding image sensor RGB gain register. WSC2810is responsible to generate the OSD(On-Screen Display) menu, improve the frame rate and enhance effect of image display. MCU is responsible to control the whole system. The design of the system has advantages at cost-effective, real-time, low power consumption, can be applied to many industrial inspections and monitoring system in high definition.The results show that the system of the performance indicators to meet the design objectives. Auto exposure, auto white balance, auto focus are good. The effect of image display can be adjusted by man-machine interface-OSD menu. System can achieve60frames/sec, when the output is1080P(1920X1080) resolution.