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梦游也逍遥

新虫 (小有名气)

[求助] USGS上下载的level 1产品需要进行哪些预处理

从USGS网站上下载的level 1 产品是只经过辐射矫正的吗,有没有用地面控制点进行过几何校正
我要用它来反演土壤盐度的话需要进行哪些预处理呢

以下是我从其他网站粘过来的
Landsat 5 TM Products - processed by the Level 1 Product Generation System (LPGS)
   Terrain Correction (Level 1T) ** The Level 1T (L1T) data product provides systematic radiometric and geometric accuracy by incorporating ground control points*, while also employing a Digital Elevation Model (DEM) for topographic accuracy. Geodetic accuracy of the product depends on the accuracy of the ground control points and the resolution of the DEM* used. For locations outside the United States, the accuracy of a terrain-corrected product will depend on the availability of local ground control points (GCPs), as well as the quality of the best available DEM. Scenes that have a quality score of 9 and less than 40 percent cloud cover will be automatically processed, and any archived scene, regardless of cloud cover, can be requested for processing through GloVis or Earth Explorer. *Ground control points used for Level 1Terrain correction come from the GLS2005 data set. DEM data used for terrain correction include SRTM, NED, CDAD, DTED, and GTOPO 30. **While most data available at no charge will be processed as Level 1T (precision and terrain corrected), certain scenes do not have ground control or elevation data necessary for precision or terrain correction, respectively. In these cases, the best level of correction will be applied (Level 1G-systematic).
    Systematic Correction (Level 1G) The Level 1G (L1G) data product provides systematic radiometric and geometric accuracy, which is derived from data collected by the sensor and spacecraft. The scene will be rotated, aligned, and georeferenced to UTM map projection.Please be aware that TM Level 1G products may require additional image geometric correction and/or co-registration to known ground control points (GCPs).

这里面提到了level 1T产品经过辐射矫正,地面控制点几何校正和高程校正
我是想知道,我在USGS上点击下载的Level 1 product 与上面提到的 Level 1T的性质一样吗
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Dawn2586

银虫 (著名写手)

【答案】应助回帖

感谢参与,应助指数 +1
没有用控制点校正,但是应该做个基本的校正。
原来可以这样
2楼2013-11-04 20:34:54
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minzi.wang

新虫 (初入文坛)

【答案】应助回帖

只是做系统的几何和大气较正而已
3楼2013-11-08 06:40:07
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