基于光线追踪的尺度效应分析

Scale Effect Analysis Based on Ray Tracing

以光线追踪为基础研究尺度变化对图像属性的影响。通过选取地物模型和构建实验场景,实现多分辨率序列图像的模拟仿真。对图像的信息熵、自相关系数、地物覆盖率进行计算和分析,得到以下结论:地物的颜色属性与尺度无关;当图像分辨率降低到一定程度后,图像将会发生失真现象,而当图像分辨率提高到一定程度后,图像的属性将只有很少变化;在不失真范围内,随着图像分辨率的降低,地物覆盖率也随之降低。该结论与传统方法分析的结果趋势相同,但传统方法产生的图像会在更高分辨率时发生失真现象,表明该方法可有效避免图像重采样误差的干扰。

This paper proposes a new way to study the effect of scale change on image attribute based on ray tracing technology. A series of multi-resolution images are simulated through the feature model selection and scene design. The results of entropy, autocorrelation coefficient, coverage rate indicate that color is unrelated to scale; distortion occurs when image resolution reduces excessively meanwhile little changes when resolution improves to a certain level; coverage rate decreases as the resolution decreases within the distortion range. The proposed method has the advantage that it is unaffected by the error of resample method compared with tradition methods.