4.01.8 Compress to GeoTIFF format (image/ raster)

The GeoTIFF format can be quite large in some instances so the ability to compress and lower the size of the file saves time while maintaining its original quality.

From a singleband raster GeoTIFF (i.e. rainfall, digital elevation model):

  1. Open QGIS (v2.18) and add your singleband raster GeoTIFF
  2. In the main QGIS window go to Raster > Conversion > Translate (Convert Format)…
  3. Complete the following fields:
    • Input Layer: singleband raster GeoTIFF
    • Output file: save to your working folder
    • Creation Options: tick this on and select the “High compression” profile (do not use “JPEG compression” as this will alter your singleband raster pixel values)
      singlebandcompress
  4. This method usually compress the file size close to half of the original GeoTIFF size
  5. Follow section 4.01.6 to upload the compressed singleband raster GeoTIFF to GRID

From a multiband raster GeoTIFF (i.e. satellite imagery, topographic map):

  1. Open QGIS (v2.18) and add your multiband raster GeoTIFF
  2. In the main QGIS window go to Raster > Conversion > Translate (Convert Format)…
  3. Complete the following fields:
    • Input Layer: multiband raster GeoTIFF
    • Output file: save to your working folder
    • Click the “Edit” symbol editsymbol and add in the following text after “gdal_translate”
      • -co COMPRESS=JPEG -co PHOTOMETRIC=YCBCR -co TILED=YES                                                                                                                                  multibandcompress

From an ArcGIS grid raster to a multiband raster GeoTIFF (i.e. satellite imagery, topographic map):

  1. Open QGIS (v2.18) and add your ArcGIS grid raster
  2. In the main QGIS window go to Raster > Conversion > Translate (Convert Format)…
  3. Complete the following fields:
    • Input Layer: ArcGIS grid raster
    • Output file: save to your working folder
    • Creation Options: tick this on and select the “High compression” profile (do not use “JPEG compression” as this will alter your grid raster pixel values)     gridrastercompress
  4. This method usually compress the file size close to half of the original GeoTIFF size
  5. Follow section 4.01.6 to upload the compressed singleband grid raster GeoTIFF to GRID

Troubleshooting:

If your raster uploads successfully but does not display the most likely case is the raster is not in a compatible data type (i.e. 8-bit)

  1. Go back into QGIS and add your compressed raster
  2. In the main QGIS window go to Raster > Conversion > Translate (Convert Format)…
  3. Complete the following fields:
    • Input Layer: compressed raster
    • Output file: save to your working folder
    • If your raster values are between 0-255 use the following method
      • Creation Options: tick this on and select the “High compression” profile (do not use “JPEG compression” as this will alter your raster pixel values)
      • Click the “Edit” symbol editsymbol and add in the following text after “gdal_translate”
        • -ot Byte                                                                                                                                                                                                                                            rasterbytecompress
    • If your raster values include decimals and/or negatives use the following method
      • Click the “Edit” symbol editsymbol and add in the following text after “gdal_translate”
        • -ot Float64 -co COMPRESS=DEFLATE                                                                                                                                                                                 rasterfloat64compress