TIMS图像处理中去相关扩展的解析及其应用

The Analysis of Decorrelation Stretch of Thermal Infrared Multispectral Image Processing and Its Application

本文基于数学分析和几何解析，结合ＴＩＭＳ图像的信息特征，对去相关扩展图像处理方法的机理进行了综合分析。分析结果表明，去相关扩展增强了原始图像中相关程度较低的那部分信息，增大了地物的光谱反差，提高了图像的地质解译效果。笔者结合局部地区的研究成果，说明经去相关扩展处理后的ＴＩＭＳ图像可提供详细、准确的岩石地层单元信息，是当前大比例尺遥感地质填图和区域找矿的一种有效新手段。

Abstract Based on the analysis of mathematical concept and geometric transformation, the author consider that the decorrelation stretch can selectively exaggerate the least correlated port of thermal multispectral image information, and enhance the spectral contrast of different ground materials. It is one of the effective methods to enhance the highly correlated images.The information of a thermal infrared multispectral image mainly include two parts: surface temperature and emissivity. In principle, the surface temperature is the dominant information. For the temperature of terrestrial surface is commonly less than 30℃, the thermal infrared multispectral image data are always highly correlated from one channel to the next. It is unfavourable for the extraction and analysis of the thematically geological information. The decorrelation stretch, which tend to increase the saturation and affect the hues little, is usful in exaggerating the poorly correlated emissivity information of thermal infrared multispectral image data, rather than the highly correlated surface temperature information.The paper presents the effectiveness of decorrelation stretch image with an example in extracting lithostratigraphical information by use of the information about the composition(i. e.emissivity),rather than the surface temperature.