Le samedi 30 avril 2016 22:52:00, Gunnar Blom a écrit : > Hi, > > I've found a possible bug in GDAL 2.1 RC4 and the MBTiles driver. > > I have the following image that I'm geo > referencing: http://imgbox.com/tLFn3Auq > If I'm using the follwing code to warp the image based on a > GeoTransform, it works > well: https://gist.github.com/gunnarblom/9d73aa4358f3dafe2fd6808f7d4e9f41 > ...and it produces the following image which is > correct: http://imgbox.com/TrzlXk4P > (note: as the target coordinate system is Apple's own in MapKit, the y-axis > is reversed and therefor the negation of the two last parameters in the > GeoTransform before warping) > If I'm using the following code to > create MBTiles: https://gist.github.com/gunnarblom/76364b6bc8c0ff48dcf9fb8 > 1a5fdc060 ...but for some images/GeoTransforms it produces > artifacts: http://imgbox.com/Gd15nfaP (three artifacts along the sides) > (note: this GeoTransform is based on WGS84-coordinates instead of Apple's > coordinate system above in the regular image warp) > This error can be very strong on other images, it seems stronger the more > skewed the transform is (example with a dummy-test I did with a random > image: http://imgbox.com/FAWJj0eC) > What do you think can cause this bug?
I'm not sure. Does changing the GDAL_CACHEMAX configuration option changes the result (value in megabytes. default value is 5% of the total RAM) ? Can you reproduce with gdal_translate ? > > Thanks! > > Regards, -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/gdal-dev
