[Mapit] Raster data in "info"

[Bernhard Herzog]

Hi,

VAN DEN BUSSCHE FA PREF31 <FA.VAN-DEN-BUSSCHE at haute-garonne.pref.gouv.fr> writes:

> But I would like to know how to realize the tiles in the easiest way.
> My organization uses, for GIS, the WindowsAPP "Geoconcept". My maps are very
> numerous (4Kmx4Kmin 1:25000, TIFF format, about 101 different files) and I
> have no time to spend to convert/calculate any "info" file (my is job is NOT
> only in computers).

Well, you'll either have to generate an info file for MapIt! or extend
MapIt! to support whatever format the information you have is in.
Generating the info file will probably be far easier.

> What is the good way.
> The original import file for the rasters is a text file with, for each line,
> the file name of the TIFF file, the x and y coord of the center of this
> tile.

It seems to me that with the information you have about the tiles, it
should be fairly simple to write a script that reads the text file you
described and produces an info file for MapIt!.

You already have the coordinates of the centers of the tiles so you can
probably calculate the coordinates of the corners from that (assuming
the other information you have is enough to determine the size of a tile
in that same coordinate system).

The other thing to do would probably be to rename the files to match the
names expected by MapIt!. E.g. for an entry in the info file like

# [6,5]
2000
2000
2400
2400

the filename would have to be 6x5.png (or .tif).

The Python Imaging Library used by MapIt! can read some tif files but
doesn't support all of TIFF's possibilities, so you may have to convert
the files to a different format as well, such as PNG.

Regards,

   Bernhard

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