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I need to down-sample a map to new map with less resolution NOT for overview BUT to new map file with smaller size

I need to do that with gdal Utils

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you can use gdalwarp for that, with the -tr parameter to set the output pixel size. For example, with input cell size of 10 m resampled to 50 m (so 25 times smaller in number of pixels)

gdalwarp -tr 50 50  -r average raw_image.tif resampled_image.tif

note that you can also use gdal_translate, but then with less control on the resampling method but the advantage of being able to use more option on the output image (such as compression)

gdal_translate -co COMPRESS=LZW -outsize 20% 20% raw_image.tif resampled_image.tif

UPDATE: with the release of gdal v 2.0, additionnal resampling method became available with gdal_translate. You can thus also use the -r average option

-r {nearest (default),bilinear,cubic,cubicspline,lanczos,average,mode}: (GDAL >= 2.0) Select a resampling algorithm.

  • can you give me an example? – Eli Alali Jan 28 '15 at 16:12
  • how can I control the average window? – Eli Alali Feb 4 '15 at 15:32
  • it will be the average of the pixel with their center in the new pixel. – radouxju Feb 5 '15 at 6:31
  • Creation options can be specified with both gdal_translate and gdalwarp. SO either way you can specify compression settings. – Pete Jun 8 '17 at 21:07
  • you have the same creation options, but not the same resampling options – radouxju Jun 9 '17 at 17:04

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