Thanks Even I am assuming that even in doing this there may still be an issue with differentiating between pixels of pure black and this 0 'no-data' value in an 8 bit band where raster min gives 0 and raster max gives 255.....ah well.
There is another question and I have noticed that the dataset created from AutoCreateWarpedVRT has different raster min and max values. One of the rasters (a single UInt16 band, rotated) has a raster min of 337.0 and a raster max of 872.0 when computed using ComputeRasterMinMax(). However the AutoCreateWarpedVRT dataset created from this original dataset has a min of 0.0 and a max of 772.0, why????? My plan (using your idea) of setting the no-data value to 0.0 would work on the original dataset as the minimum is > 0.0 and therefore 0.0 could be filtered out; however due to the conversion by the AutoCreateWarpedVRT, 0.0 is now a valid colour and once again falls into the issue of whether 0.0 is 'no-data' or a genuine colour. Thanks Martin -- View this message in context: http://osgeo-org.1560.x6.nabble.com/Remove-Black-Areas-From-Rotated-Images-tp5167665p5167762.html Sent from the GDAL - Dev mailing list archive at Nabble.com. _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
