GDAL2TILES

Analogue of gdal2tiles.py on C#. I've rewritten it for my university project, so now it only works like gdal2tiles.py with the following arguments (zoom values and paths are here for example):

input.tif outputDirectory -s EPSG:4326 -p geodetic -r cubicspline --tmscompatible -z 10-14

It also doesn't make any output/progress reporting at the moment and doesn't write openlayers.html/.kml/etc, only .png tiles in tms structure. Later I plan to develop this to support all original's gdal2tiles functionality.

Project is build in VS2017, .NET Framework 4.7.2, targeting x64 systems.

Usage

To use Gdal2Tiles class you should add this file to your project. It depends on Gdal's C# bindings, that you should reference in your project and configure before calling Gdal2Tiles.cs methods. I used GDAL.NET in my example and I recommend you to do the same, yet it would work with other versions of Gdal bindings too. So, the complete algorithm looks like this:

1. Add Gdal's c# bindings, Gdal2Tiles.cs file and using OSGeo.GDAL directive to your project;

2. Configure Gdal in your code before calling Gdal2Tiles methods (for GDAL.NET nuget package call GdalConfiguration.ConfigureGdal(); and if you don't want to use GdalConfiguration class, you can call Gdal.AllRegister() directly, but you should specify environment variables before by yourself);

3. Call Gdal2Tiles.CropTifToTiles method, which takes following parameters:

   • string inputFile - full path to input GeoTIFF in EPSG:4326 (current version, plan to expand functionality later);
   • string outputDirectory - full path to output directory, in which zoom directories with data will be created;
   • int minZ - minimum cropped zoom, which you want for your data;
   • int maxZ - maximum cropped zoom;
   • OSGeo.Gdal.ResampleAlg resampling - resampling algorithm (currently CubicSpline/Cubic only supported);

Also, it’s worth mentioning, that CreateBaseTile() and CreateOverviewTiles() methods use Parallel.For/Parallel.ForEach, so if you don’t like it you’d probably will need to rewrite these three lines with usual foreach/for loop.

TODO

• Fix tile borders error from original gdal2tiles script (error probably happens in GeoQuery method);
• Replace gdal’s reading and writing methods with something more performant (at least System.Drawing.Image, Bitmap or Graphics);
• In ideal, fully replace gdal (GeoTiff’s metadata probably can be read with help of libtiff.net, need tests);
• Support all functional of original script;
• Progress reporting;

Contributing

Feel free to contribute, make forks, change some code, add issues etc.