Designing And Realization Of High Dynamic Range Imaging Equipment Based On FPGA

High dynamic range (HDR) image’s brightness range is very wide which canrecord and express more illumination details. High dynamic range imaging system hasbroad application prospects and demands in many areas. Since the current HDRimaging systems are too expensive to widespread use and pictures got by ordinarydigital camera usually can’t meet the HDR imaging algorithm requirements.This paperis trying to develop a low-cost networked digital imaging equipment with a supportingsoftware system to realize a low-cost and efficient HDR imaging system.Combine the general structure of digital imaging system, SOPC control technology,HDR imaging algorithm with the general application requirement, we analyze thefunctional requirements of the HDR imaging equipment and proposed the overallsystem implementation based on low-cost CMOS image sensor, FPGA developmentboard and network interface. After studying the work and control mode of theMT9N001, the image sensor configuration mode, the exposure control mode, imagecapture mode, Bayer pattern reconstruction mode and SDRAM image cache mode hadbeen designed to realize displaying the real time view on the VGA monitor,automatically temporal multi-exposure control and image caching control. Then bydeploying the Nios II system and creating self-definition components, the imagingequipment control SOPC system has been created. The Nios II software has beendeveloped to automatically gather, save and upload pictures with different exposuretime. After system functional test, the results met the design requirements.The realized imaging equipment can make the sensor automatically temporalmulti-exposure and get a serial of LDR images with the almost same light condition butwithout relative displacement that can hardly get with ordinary digital camera, and canimprove the efficiency and quality of the HDR imaging algorithm and also can reducethe cost of HDR imaging equipment, promote the popularization of HDR imagingapplication. The research work has some practical value.