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I'm looking for a way to cut a larger number of neighboring aerial raster images (each sized 1x1 km, resolution 10 cm per pxel) into four smaller raster images (size 500 x 500 m). I haven't done this before, is there a (preferably QGIS-based) way to do this (semi-)automatically?

I don't need any "slippy map"-like tiles - this is only necessary because my colleagues use a rather exotic and antique CAD software that can't handle larger image sizes... (and our state geodata department doesn't sell smaller custom sized tiles any more)

Thanks a lot!

  • are you looking to scale the images proportionally smaller from 1km to 500m? - retaining all the 1km features...or are you looking to clip the image to a 500m size loosing 500m of data? – MDHald Jan 8 '14 at 15:53
  • I need to cut about 40 raster images (sized 1x1 km) into 160 images (sized 500 x 500 m) without reducing the resolution. Some sort of batch process would really help, I just don't really know where to look. All tutorials I could find just address cutting a single larger image into smaller pieces, e.g. with vector lines. – SAnderka Jan 9 '14 at 7:39
  • Just pick your favourite tutorial, implement it as a script and then wrap the code in a loop to iterate over all of your larger files. – MappaGnosis Jan 9 '14 at 8:14
  • Hm, the tutorials I found turned out to be less helpful than expected, and I'm haven't really used scripting before. I'm also not quite sure if I'm using the right terminology in my search. What I'm trying to achieve is more or less "reversed mosaicing", how would you call this process? "Clipping" is almost always used synonymous with "cropping" in my search results, and I don't want to crop anything away... I'm a bit lost right now. – SAnderka Jan 9 '14 at 8:42
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You may have luck using the Split Image tool in the Orfeo Toolbox in QGIS processing toolbox.

Simply download and install the Orfeo toolbox and in QGIS>View>Panels>Toolbox expand the Orfeo Toolbox (Image Analysis) dropdown menu in the Processing toolbox. Select Split Image and select your settings in the pop up window.Location of toolbox

here is an image of where to find the split image tool in the processing toolbox. Split Image Orfeo Toolbox

  • @sanderka did this work? – MDHald Jan 16 '14 at 4:46
  • Sorry for the delay. It took some time to get OTB up and running in my office QGIS installation. Sadly, the "split image" tool only seems to split a multi-band image in several single-band images with identical extents. It does not offer any options to cut a single raster image into e.g. quarters (which is what I need). – SAnderka Jan 23 '14 at 12:34

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