摘要
高动态范围图像(high dynamic range image)指的是扩大了景物可分辨的光照范围的图像。在HDRI成像中动态范围是难以量化测量的,必须将对动态范围的计算转化为其它易于计算的像质评价函数。HDRI图像的像质评价和普通图像的像质评价存在着较大不同。比较了几种像质评价的方法后,提出了利用图像的熵作为标准进行高动态范围成像评价的方法。利用一种自然图像的概率模型对图像的熵与成像动态范围之间的关系进行了数值模拟,得到了具有普遍意义上的理想成像动态范围的计算公式,公式指出了对自然景物完善成像所需的最大动态范围;给出了图像熵与动态范围之间的关系。利用这种关系可以经由计算图像的熵来对系统的动态范围特性做出评价。这种评价方法在指导高动态范围成像系统的设计,以及高动态范围成像系统的测试中将发挥重要的作用。
High dynamic range image（HDRI） means the image with wide illumination range.It＇s rather hard to calculate dynamic range directly,evaluation methods of image quality can be used to evaluate image dynamic range indirectly.After comparing some kinds of image quality evaluation methods,the evaluation method with image entropy is proposed.This is not a new method for general image evaluation,but for HDRI it is a new method.The relationship between image entropy and dynamic range is discussed with data simulation process.A statistical model of natural image is used in this simulation.The conclusion can be drawn from simulation results that the HDRI system has a maximum dynamic range for perfect imaging.And the relationship between entropy and dynamic range is also expressed with a simple formula.So the HDRI system can be evaluated by image entropy with this method.This evaluation with HDRI entropy will take great effect in the field of HDRI system design and HDRI device test.
出处
《光学技术》
CAS
CSCD
北大核心
2010年第1期106-110,共5页
Optical Technique
