摘要 图像增强技术能够有效地提高低照度图像能见度。针对现有图像增强方法引入的对比度过度增强和欠增强的问题,文中提出了面向低照度图像增强的双曝光融合处理算法。利用照度估计技术得到图像融合的权值矩阵,通过摄像机响应模型合成双曝光图像,找到最佳曝光率使合成图像在曝光不足的区域曝光良好。根据权值矩阵将输入图像与合成图像融合,得到增强结果。低亮度像素的场景照明映射在各通道有不同的体现,为了避免因差距过大导致亮度分量不够准确,文中定义了低亮度像素和亮度分量以计算最佳曝光率。实验结果表明,所提方法比已有方法具有更小的亮度失真和更短的运行时间。 Image enhancement techniques can improve the visibility of low-light image effectively.In view of the problem of over-enhancement and under-enhancement of contrast introduced by existing image enhancement methods,a dual-exposure fusion algorithm for low-light image enhancement is proposed.The weight matrix of image fusion is obtained by the illumination estimation techniques.The dual-exposure image is synthesized by the camera response model.The best exposure ratio is identified so that the synthetic image is well-exposed in the regions where the original image is under-exposed.The enhanced result is obtained by fusing the input image and the synthetic image according to the weight matrix.The scene illumination map of low illuminated pixels is reflected differently in different channels.In order to avoid the inaccuracy of brightness component caused by too large difference,the low illuminated pixels and brightness component are defined to calculate the optimal exposure ratio.Experiments show that compared with the existing methods,the proposed method has less brightness distortion and running time.
机构地区 上海工程技术大学电子电气工程学院
出处 《电子科技》 2021年第6期34-39,共6页 Electronic Science and Technology
基金 上海市自然科学基金(17ZR1411900) 上海市信息安全综合管理技术研究重点实验室项目(AGK2015006) 上海工程技术大学研究生创新项目(18KY0208)。
关键词 图像增强 低照度 对比度 曝光融合 权值矩阵 图像融合 亮度 最佳曝光率 image enhancement low-light contrast exposure fusion weight matrix image fusion brightness the optimal exposure ratio
