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ogr2ogr cheatsheet

Fri 07 February 2020

ogr2ogr commands

ogr2ogr cheatsheet: https://www.bostongis.com/PrinterFriendly.aspx?content_name=ogr_cheatsheet

To convert a projected shapefile (GDA94 / MGA zone 50) to WGS84:

ogr2ogr -s_srs EPSG:28350 -t_srs EPSG:4326 dest_unprojected.shp source_projected.shp

To obtain summary information about a dataset:

ogrinfo -so sourcedata.shp layername1 [layername2 ...]

To convert a shapefile to GeoJSON using WGS84 projection:

ogr2ogr -t_srs EPSG:4326 -f GeoJSON output.geojson source.shp

Raster (GeoTIFF) compression using GDAL

Source: http://blog.cleverelephant.ca/2015/02/geotiff-compression-for-dummies.html

gdal_translate: https://www.gdal.org/gdal_translate.html

gdaladdo: https://www.gdal.org/gdaladdo.html

More info: http://docs.geonode.org/en/master/tutorials/advanced/adv_data_mgmt/adv_raster/processing.html

Compression steps:

gdalinfo source.tif
# Use gdal_translate to implement JPEG compression:
gdal_translate -co COMPRESS=JPEG -co TILED=YES source.tif output.tif
# Use the YCBCR colour space during compression (if it has bands, we need to use the first three and discard any fourth alpha band):
gdal_translate -b 1 -b 2 -b 3 -co COMPRESS=JPEG -co PHOTOMETRIC=YCBCR -co
TILED=YES source.tif output.tif
# Add overviews to the compressed image:
gdaladdo --config COMPRESS_OVERVIEW JPEG --config PHOTOMETRIC_OVERVIEW YCBCR --config INTERLEAVE_OVERVIEW PIXEL -r average output.tif 2 4 8 16 32