Global Positioning System Reference
In-Depth Information
possibly, OSM validation. Although this process takes some time, it secures
the production and, in the long run, it's also a good idea to archive the
map sources. This toolchain harmonization can implicitly detect unknown
problems and they can be fixed as they occur. Each tool and each map file
creates a new version and every change can cause surprises.
When trying to zip the cleaned file with osmosis
D:\<full path>\tools\osmosis-0.37\bin\osmosis.bat
--rx germany.clean.osm --wx germany.osm.bz2
one of these surprises pops up:
org.openstreetmap.osmosis.core.OsmosisRuntimeException:
Node 104936 does not have a version attribute as
OSM 0.6 are required to have. Is this a 0.5 file?
The exception describes the problem: the parser was initially developed
with OSM 0.5 files and since the requirements have changed, the tools
need to be adapted. After this exception from osmosis, the OSMparser has
to be modified and the delivery has to be processed again.
This demonstrates the necessity to test a compilation with a smaller
file through the full chain before using it on really big files. After sucient
understanding and testing (development), you can run a number of parsing
steps on a full country file (testing) and then integrate the steps in your
map compiler (production).
Note that a new switch was added to the parser: with -clean , the file is
cleaned from unnecessary OSM attributes, while -cleanAll would remove
all attributes. The implementor needs to be aware that the -clean switch
is already part of the map compiler and that a new behavior could affect all
products. The OSMparser is not a tool for map production like osmosis. So
the latter option ( -cleanAll ) should only be used after the file has passed
all OSM tools. With every change in the toolchain, the map engineer has to
check backward compatibility issues. Take some time to load a RGB-NW.osm
file into JOSM, modify the map, and observe the changes in a text editor
or with a diff tool.
Batch Processing
The simple processing chain takes eight to ten hours to get the Germany
file in place, and the consumed disk space is a factor 23 larger than the
initial delivery. The CPU load is high during the process, and it might be a
good idea to include cooling pauses, depending on the hardware used (see
Table 7.4).
The parser is just a small, yet effective, tool that a map engineer can
use in a map compilation and easily add more functionality, for example,
a -stats switch (see page 107) to collect statistics.
Or it can serve as a
 
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