@Matt
Maps were georeferenced in QGIS using trig stations on the maps against the historic trig dataset from LINZ.
Map outlines (for non-rectangular survey-district based maps) were digitised manually in QGIS from the georeferenced mapsheets.
GDAL was then used to automatically:
- Cut mapsheets to the vector survey district boundary
- reproject the maps to NZTM2000
- ensure all maps have the same RGBA format (the source files did not)
- mosaic the individual sheets into a single .vrt
- tile the maps to 256*256 x,y,z tilesets
Imagemagik was used to:
- palettise the resulting RGB tile images to make filesizes manageable
(2025/09/08 09:22)
Map outlines (for non-rectangular survey-district based maps) were digitised manually in QGIS from the georeferenced mapsheets.
GDAL was then used to automatically:
- Cut mapsheets to the vector survey district boundary
- reproject the maps to NZTM2000
- ensure all maps have the same RGBA format (the source files did not)
- mosaic the individual sheets into a single .vrt
- tile the maps to 256*256 x,y,z tilesets
Imagemagik was used to:
- palettise the resulting RGB tile images to make filesizes manageable
(2025/09/08 09:22)