Preferred offline raster format, five months from now?

[tommi]

Hi Menion,
my statement is derived from these posts:
viewtopic.php?f=27&t=2031&p=13044&hilit=4GB#p13044
viewtopic.php?f=25&t=261&p=965&hilit=4GB#p965
However I find it not so useful to use maps >2GB as this will split users/phones which can use them and those who can't.

[mark03]

Hi Menion,

From my perspective the actual limit should not matter that much.  I will be making maps much bigger than 2 or 4 GB anyway.  But the GEMF spec defines how to split one map across files like foo.gemf, foo.gemf-1, foo.gemf-2, and so on.  Does Locus support that part of the spec?

[stebu]

Hi Menion,

From my perspective the actual limit should not matter that much.  I will be making maps much bigger than 2 or 4 GB anyway.  But the GEMF spec defines how to split one map across files like foo.gemf, foo.gemf-1, foo.gemf-2, and so on.  Does Locus support that part of the spec?

I tested my GEMF converter with split files, but each file was much smaller than 2 GB.
I'm almost positive, that I tested that map on Locus.
And I'm positive, that each map I that tested in Locus worked fine.

[mark03]

Success!

Over the weekend I generated topo mosaics covering half the state (about 800 source GeoPDFs), tiled at zoom levels 9 to 16.  On my phone's screen (Samsung Vibrant), zoom level 16 is somewhat zoomed-in compared to the paper maps, but still sharp thanks to the new GeoPDF scans which are typically at 500 dpi--much better than the old DRG GeoTIFFs.  Panning and zooming is still snappy, even with the map split across several 2-GByte GEMF files.

This is a good way to find errors in the USGS georeferencing.  I've found at least two quads with the wrong coordinates, and sent feedback to the people at the historical maps collection.  Their database is also missing ~30 quads here and there across the state, which I hope will be filled in this summer.

I think I can probably fit the entire state in about 20 GBytes.  I am using JPEG tiles for considerable space savings over PNG, with very little loss in quality.

[kerenoc]

So the whole thing is done using open-source tools, and best of all, it's entirely at the command line--no GUIs.  Scriptable FTW  

I'm trying to process the tracks from my last summer vacation in Soutwest USA and I need to re-process the USGS maps I had stichted using various tools (including Maptiler and Mobac). As I'm also a Python user, I'm interested in the scripts that seems to automate this process. Is there any chance that they could be shared, in an open source spirit?

[stebu]

I'm trying to process the tracks from my last summer vacation in Soutwest USA and I need to re-process the USGS maps I had stichted using various tools (including Maptiler and Mobac). As I'm also a Python user, I'm interested in the scripts that seems to automate this process. Is there any chance that they could be shared, in an open source spirit?

Check the GEMF site //http://www.cgtk.co.uk/gemf , it has a link to some Python scripts.

[kerenoc]

Thanks for the link. Still searching for the code specific to USGS maps (especially to remove maps collars).