• 论文 •

### 基于谱间特征和归一化指数分析的城市建筑用地信息提取

1. 福州大学环境与资源学院, 福建福州 350002
• 收稿日期:2004-08-20 修回日期:2004-11-26 出版日期:2005-04-15 发布日期:2005-04-15
• 作者简介:徐函秋(1955-).男.汉族.江苏射阳人.博士.教授.博导主要从事环境与资源遥感应用研究.己在含SCI收录的国内外刊物上发表论文数十篇.Email:fdy@public.fz.fj.cn
• 基金资助:

国家自然科学基金资助项目(40371107)福建省科技三项资助项目(K03011)

### Fast information extraction of urban built-up land based on the analysis of spectral signature and normalized difference index

XU Han-qiu

1. College of Environments and Resources, Fuzhou University, Fuzhou 350002, China
• Received:2004-08-20 Revised:2004-11-26 Online:2005-04-15 Published:2005-04-15

Abstract:

This paper studies the principles and method of fast remote-sensing information extraction for urban built-up land, taking Fuzhou city as an example. With the detailed analysis and clarity of several existing normalized difference indices, the study selects three indices, Normalized Difference Built-up Index (NDBI), Modified Normalized Difference Water Index (MNDWI) and Soil Adjusted Vegetation Index (SAVI) to represent three major urban land use/cover classes, i. e. , built-up land, water body and vegetation, respectively. The three index images are generated from a Landsat ETM + subscene of Fuzhou city and then used as three bands to compose a new image. This dramatically compresses the original eight-band ETM+ image into a three-band image, reduces band correlations and data redundancy, thus significantly simplifiying the band spectral analysisprocedures. The spectral signature analysis only needs to be performed on this three-index composite image and the signature differences among the three major urban land use/cover classes are revealed much easier than being done with multi-bands. Based on the revealed signature differences, the built-up land is finally extracted through a simple logic calculation. The result achieves a 91.3% overall accuracy. Therefore, the method is a fast and accurate one for the remote-sensing information extraction of urban land use without human interference. In addition to the above built-up land information extraction study, the paper proposes a Modified Normalized Difference Water Index (MNDWI) based on the NDWI of Mcfeeters (1996) , which uses MIR wavelength (ETM + band 5) instead of NIR wavelength to construct the index. The replacement largely enhances the contrast of the water bodies with the other land use/cover classes and reduces the spectral confusion with the other classes. Therefore, the MNDWI is more suitable for delineating features of polluted urban rivers/lakes. The advantages of using SAVI instead of NDVI in the urban study are also discussed in this paper.