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I wish to produce a large image. As a base use cloud free regions of multiple Landsat images. I wish to keep the bands and be able to work with the generated mosaic just like a "normal" Landsat image. What ways would you propose to archive a satisfying result? I am on Linux/Qgis

  • Are trying to mask the clouds or do you want to create a cloud free mosaic from multiple scenes for the same location? – Kersten Nov 25 '15 at 7:51
  • Exactly , i wish to crate a cloud free mosaic from multiple scenes for one large region. – kwai Nov 25 '15 at 7:53
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You can also build a virtual raster file (vrt) with GDAL

Add all tif in folder to vrt

gdalbuildvrt C:/tifs/my_vrt C:/tifs/*.tif

Build a pyramid for increased performance

gdaladdo -r AVERAGE --config BIGTIFF_OVERVIEW=YES -ro --config COMPRESS_OVERVIEW DEFLATE --config PREDICTOR_OVERVIEW 2 --config ZLEVEL 9 C:/tifs/my_vrt.vrt 2 4 8 16 32 64

You can use the GDAL VRT builder from QGIS menu Raster > Miscellaneous > Build Virtual Raster Catalog ... You can also make pyramids from the same Miscellaneous menu.

  • i very appreciate your answer but isn't there a way without using GDAL? This exceeds my knowledge of GIS by far. – kwai Nov 25 '15 at 10:25
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    You can use the GDAL VRT builder from QGIS menu Raster > Miscellaneous > Build Virtual Raster Catalog ... You can also make pyramids from the same Miscellaneous menu. – Jakob Nov 25 '15 at 10:38
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You should use the gdal library outside Qgis

Gdal merge

ps : If your outpout tiff is more than 4g make sure to add the BigTiff option

co options

  • I have to cut large parts of the base images because they overly each other. is this possible in Gdal? i have never worked with it before – kwai Nov 25 '15 at 8:16
  • with gdalwarp you can apply clipping yes – julsbreakdown Nov 25 '15 at 11:31

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