Image statistics for material perception
Image statistics for material perception
复制标题
物质感知的图像统计
DOI：
10.1167/4.8.123
复制
发表时间：
2004
影响因子：
1.8
通讯作者：
Lavanya Sharan
中科院分区：
文献类型：
--
作者：
E. Adelson;Yuanzhen Li;Lavanya Sharan
我们不可能知道一个孤立的朗伯斑块的反射率，我们必须将它与其他相邻的斑块进行比较。然而，当我们看到一个更复杂的材料，如布，灰泥，或皱巴巴的纸，我们可以惊人地善于判断的波纹，即使是孤立的观察。这怎么可能？当光线照射到复杂的表面时，它可以在被吸收之前反射或折射多次。相互反射的图案导致取决于反射度和透明度的纹理质量。此外，镜面反射在深色材质上更加突出，在浅色材质上被稀释。为了量化可用的统计数据，我们拍摄了许多材料的数字照片，并在缩放到标准平均亮度后，我们确定了可能有用的纹理属性。在我们的发现中：光材料的功率谱福尔斯比暗材料下降得更陡。亮度直方图信息量很大，其中方差、偏斜和百分位数统计数据可用于诊断表面反射率属性。小波带间的相位相干性（Portilla和Simoncelli的纹理算法使用的结构度量）是相干性的诊断。我们将讨论各种基于像素和基于小波的纹理测量，并建议如何将它们用于人类视觉。
It is impossible to tell the albedo (reflectance) of an isolated Lambertian patch; we must compare it to other, neighboring patches. However, when we look at a more complex material, such as cloth, stucco, or crumpled paper, we can be surprisingly good at judging the albedo, even with isolated viewing. How is this possible? When light strikes a complex surface, it is can be reflected or refracted many times before being absorbed. The pattern of interreflections leads to textural qualities that depend on the albedo and the translucency. In addition, specular reflections are more prominent against dark materials, being diluted when seen on light materials. To quantify the available statistics, we took digital photographs of many materials, and after scaling to a standard mean luminance, we determined the textural properties that could be of use. Among our findings: The power spectrum falls more steeply for light materials than for dark ones. The luminance histogram is quite informative, with the variance, skew, and percentile statistics being diagnostic of surface reflectance properties. Phase coherence across wavelet bands (a measure of structure used by Portilla and Simoncelli's texture algorithm) is diagnostic of translucency. We will discuss a variety of pixel-based and wavelet-based textural measures, and suggest how they may be used in human vision.