UPDATED To clarify my previous post. I have written a small application to convert maps saved as PDF's to PNG files then tile the maps to be used in a webservice. After experimenting with the PNG Maps and updating my GDAL library to a newer version (1.9.2) Nuget GDAL in my program. I started experimenting with PDF's directly and not going through the time intensive task of converting them to PNG files. A couple of things I have noticed in switching to PDF's is that:
1) the 256 pixel tiles are of better quality.
2) the tiling process runs much faster.
I have a lot of maps to convert on a daily basis, so the speed and quality improvements are a plus. One thing that pops up on quite a few PDF's that I tile is the exception: "Cannot Find GPTS Object". This happens immediately when I go to open the dataset with the following code:
if(System.IO.Path.GetExtension(pathFile) == ".pdf" || System.IO.Path.GetExtension(pathFile) ==".png") { ds = Gdal.Open(pathFile, Access.GA_ReadOnly);// blows out on open } else { ds = Gdal.Open(pathFile, Access.GA_Update); }
I have searched quite a few hours on this exception and cannot find any documentation on it other than the source code that the exception is generated from. I was wondering if anybody had run across this before and if there is a solution to the problem.
The PDF maps are not georeferenced.