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Can anyone help me regarding the what kind of image pre-processing techniques should be used for the landsat images downloaded from http://earthexplorer.usgs.gov/ to create land-use land-cover (LULC) map?

  • sure , I just wanted to know what sort of correction and what steps should be followed to create landuse and cover map from Landsat images. – advent_udaya Apr 22 '16 at 0:50
  • What Landsat sensor are you working with? – Aaron Apr 22 '16 at 0:53
  • Actually i am doing from year 1999-2016. So, it depends on the year. Let me know about L7 ETM+ slc-off at the moment. @Aaron – advent_udaya Apr 22 '16 at 1:18
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Atmospheric correction is required for all time series studies, as indicated in your comments. Dark object (aka Dark Body) subtraction is a common method to accomplish this as long as a suitable dark object, such as a water body, exists in the scenes.

Resources:

  • In the video I see how the haziness disappeared when DOS performed.The bottom-line of the paper is Simple dark object subtraction, with or without the Rayleigh atmosphere correction, or relative atmospheric correction are recommended for classification and change detection applications. – SIslam Feb 3 '17 at 5:10
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@Mr. Che and @Aaron have given great answers regarding two different things to do, but i would like to point out that there is actually a quick and easy way to use the landsat data without dealing with implementing the fmask algorithm or doing the atmospheric correction yourself: by using the surface reflectance data processed based on Landsat data. They are available for download at EarthExplorer as well. These data have been processed so that there is no need for you to do either georegistration or atmospheric correction any more (most of the time). Plus together with the surface reflectance data they also provide various cloud masks, including fmask-based ones, so you don't need to implement the algorithms yourself.

I'd also like to answer your question by saying that there is no universal way to preprocess data for land cover and land use mapping. You always have to decide what is necessary and what is not based on your specific needs and the data you have access to. But surface reflectance data is usually a good starting point.

screenshot of EarthExplorer

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    Yes that is correct however you still can look at the land cover as a reference to see if there are changes to it. – PROBERT Apr 22 '16 at 18:17
  • @PROBERT absolutely – TonyC Apr 23 '16 at 0:56
  • Thanks @TonyC that means i can just layer stack, do some focal analysis, subset the area of interest and do classification if i m not wrong. – advent_udaya Apr 23 '16 at 6:41
  • @TonyC I think L8 OLI/TIRS data from earth-explorer is not atmospherically corrected. at least for some scene of Bangladesh so far! – SIslam Feb 3 '17 at 8:57
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P.s how to remove cloud for landsat 7 images?

You can try to use automate standalone algorithm Fmask described here.

We're looking for long answers that provide some explanation and context. Don't just give a one-line answer; explain why your answer is right, ideally with citations. Answers that don't include explanations may be removed.

  • Thanks but is there any way we can do with erdas imagine or arcgis? – advent_udaya Apr 22 '16 at 2:00
  • @Udaya_advent I recommend you to follow instructions described in Fmask site, this algorithm is very complicated to reproduce it. Besides it gives very good results in clouds and shadows masking. – Mr. Che Apr 22 '16 at 4:15

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