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oft-crop.bash crops a raster image to the extent of a certain pixel value

Usage: oft-crop.bash <input-img> <output-img> [ { value / -all } ] [ nodata-value ]

[ { value / -all } ]
   [value] = is the value of the inputfile it should be cropped to
   -all = if image should be cropped to every unique pixel value; output will be named accordingly
[nodata-value]: for this value no cropping will be done; if not provided, it is assumed to be 0 (only applicable for option -all)
  • Oft-crop.bash crops a raster image to the extent of a certain pixel value. This can be useful when, for example, one wants to produce a separate raster image for every district of a country.
  • Input image is a raster image with unique pixel values for each region of interest.
  • In the output image, the value for the region of interest is kept. All other pixels are set to 0.
  • The user can choose to either
    • do the cropping for one single pixel value
    • do the cropping for all occurring pixel values besides the nodata-value. The nodata-value can be specified with the [nodata]-option. If not specified, it is assumed to be 0. In this case, output files will carry the value they have been cropped to in their name.


1. You will need for this exercise the file landuse.shp, digitized manually with QGIS

2. Create a raster file that has the landuse class attribute of the landuse.shp file

gdal_rasterize -a newcol -l landuse -tr 30 30 shapefiles/landuse.shp results/landuse.tif

3. Extract one particular class (in that case the zone that has the label 2000)

oft-crop.bash results/landuse.tif results/lu_class.tif 2000

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