计算机辅助设计与图形学学报
計算機輔助設計與圖形學學報
계산궤보조설계여도형학학보
JOURNAL OF COMPUTER-AIDED DESIGN & COMPUTER GRAPHICS
2014年
11期
1981-1988
,共8页
张菲菲%谢伟%石强%秦前清
張菲菲%謝偉%石彊%秦前清
장비비%사위%석강%진전청
亮度掩蔽%超阈值对比度%亚阈值%梯度场
亮度掩蔽%超閾值對比度%亞閾值%梯度場
량도엄폐%초역치대비도%아역치%제도장
luminance masking%suprathreshold contrast%sub-threshold%gradient field
针对传统的对比度增强方法在对低照度图像进行处理时不能同时顾及压缩动态范围、调整亮度以及增强或保持细节等问题,提出一种基于人眼视觉感知特性的、从全局亮度映射到局部细节补偿的低照度图像对比度增强方法。首先通过非线性全局亮度映射模型压缩图像的动态范围,提高图像的整体亮度水平;然后结合人眼视觉系统的亮度掩蔽特性和超阈值对比度感知特性,非线性地调整图像的局部梯度场增强和恢复图像的局部细节;最后在目标梯度场上通过快速求解泊松方程获取增强后的图像。实验结果表明,该方法能够有效地增强低照度图像的全局和局部对比度,提升了低照度图像的视见度。
針對傳統的對比度增彊方法在對低照度圖像進行處理時不能同時顧及壓縮動態範圍、調整亮度以及增彊或保持細節等問題,提齣一種基于人眼視覺感知特性的、從全跼亮度映射到跼部細節補償的低照度圖像對比度增彊方法。首先通過非線性全跼亮度映射模型壓縮圖像的動態範圍,提高圖像的整體亮度水平;然後結閤人眼視覺繫統的亮度掩蔽特性和超閾值對比度感知特性,非線性地調整圖像的跼部梯度場增彊和恢複圖像的跼部細節;最後在目標梯度場上通過快速求解泊鬆方程穫取增彊後的圖像。實驗結果錶明,該方法能夠有效地增彊低照度圖像的全跼和跼部對比度,提升瞭低照度圖像的視見度。
침대전통적대비도증강방법재대저조도도상진행처리시불능동시고급압축동태범위、조정량도이급증강혹보지세절등문제,제출일충기우인안시각감지특성적、종전국량도영사도국부세절보상적저조도도상대비도증강방법。수선통과비선성전국량도영사모형압축도상적동태범위,제고도상적정체량도수평;연후결합인안시각계통적량도엄폐특성화초역치대비도감지특성,비선성지조정도상적국부제도장증강화회복도상적국부세절;최후재목표제도장상통과쾌속구해박송방정획취증강후적도상。실험결과표명,해방법능구유효지증강저조도도상적전국화국부대비도,제승료저조도도상적시견도。
Traditional contrast enhancement methods cannot simultaneously compress the dynamic range ,adjust the brightness and enhance or preserve the details of images on the low‐light images processing .Combining the human visual perception characteristics , a novel contrast enhancement method is proposed to enhance low‐light images via a global brightness mapping to local details compensation strategy .Firstly ,a nonlinear global brightness mapping model is employed to compress the dynamic range and adjust the overall brightness of the image .Then ,the image gradient filed is modified to enhance and restore the local details by combining the luminance masking and suprathreshold contrast perception characteristics of human visual system . Finally a new enhanced image is obtained by using a fast Poisson solver on the target gradient field .The results demonstrate that the proposed algorithm enhances both global and local contrast effectively and improves the visibility of the low‐light images .