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I am using ArcMap 10.4.1 but I am also more than familiar with QGIS.

I have a raster file (single band) from a merged grid on population statistics for Europe (please see image attached). The red cells represent on the scale 1000 x 1000 meters populated areas with a specific count, the black values represent 0 values. These are two separate raster files so far, however they're perfectly aligned meaning there are no overlaps.

I would like to compute the population potential for the grid, meaning the count of population in a certain area. Therefore, I need the 0 values also as 1000 x 1000 m raster file.

Currently, the 0 values are 1 grid with a 1000 x 1000 m resolution but no 1000 x 1000 m single tiles as I would need them.

Is there a way to "break up", "split-up" or "disaggregate" the 0 value raster file into individual cells of 1000 x 1000 m without creating an individual raster file for each cell?

The 'Split' tool does not create the output that I like, as it separates the raster into multiple files.

Map extract

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If I understand your issue, this can be done with gdal (stand alone gdal or use from QGIS). Using gdalbuilvrt you can create virtual raster templates (aka the vrt) with the extent and resolution that you want (-tr xres yres for the resolution, -te xmin ymin xmax ymax for the extent.) This will not create new rasters but xml files that you can handle like rasters in QGIS or ArcGIS.

  • I answered because gdalbuildvrt is arguably to best tools to split/merge raster without creating new ones. However, I am not sure to understand what you want to do with rasters having the same extent as their spatial resolution. Shouldn't you combine the two rasters in a single band raster if they have the same resolution and do not overlap ? – radouxju Jun 17 '16 at 12:52
  • @qradouxju Hello and thank you for your fast reply. I would like to execute a Spatial Join afterwards, summarizing all values in a raster in a circle of 50 km. – SebastianH Jun 17 '16 at 14:37
  • @qradouxju I have no time anymore to try it on friday but I will execute your proposal on Monday. Thank you in advance for your comment, I'll keep you posted. – SebastianH Jun 17 '16 at 14:43
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Just for the record, the reply below;

gradouxju was somehow right in his assumption that I should go ahead and start to combine these raster files. There was no need to 'break up' any of the cells as I mistook the single entry in the raster attribute table as a sign that I don't have individual 1000x1000 m tiles but a 'polygon-like' large raster tile. It was thus a problem caused by my own incompetence.

Sorry for the inconvenience and nevertheless thank you for the quick help!

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