Demands for the feature of high dynamic range of digital camera were seen in lots of applications of machine vision. Logarithmic image sensor supplies the hardware architecture to the requirement, but the exposure algorithm was still manual and ineffective. A high dynamic range auto-exposure algorithm based on Logarithmic image sensor was presented to meet the requirement. With field-programmable gate array, this algorithm can separate the natural scenes into region of interest and region of target. Real-time auto-segmentd exposure and Logarithmic exposure were applied to keep the detail of dark area and recover the overexposed area. The results show that the dynamic range of the image is improved significantly.%在机器视觉领域,许多应用对摄像机的动态范围提出了苛刻的要求.对数曲线响应传感器的出现为图像动态范围的提升奠定了硬件基础.然而目前针对该传感器的曝光控制均需人工操作评估,自动性、实时性差.为了解决这个问题,提出了一种基于对数曲线响应传感器的高动态范围自动曝光算法,并基于现场可编程门阵列(FPGA)并行计算在硬件上实现该算法,从而能够在图像前端实现对物理场景的实时高动态曝光.通过对感兴区间和目标区间的自适应选择,在保留阴暗区域细节的基础上实现过曝区域的复原,提升图像动态范围.
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