air quality assessment & management
Reference and User Manual
Making new overlays
New overlays to be used in map composition and thus as background maps can be generated from any georeferenced raster orgeotiff files.
Example: overlay from Google maps
This examples generates a high-resololution map around Vitoria, Brazil.
To start, created a image out of google tiles centered on the intended domain( ~50x50km ).
Next copy the procedure to create a new overlay, looking at the Brazil overlay example "Very-high-resolution image". http://aca6/RBO/rbo.php?ID=14&CLASSID=47&&WIDTH=700
Filename on the GUI is test2. The files used by mapserver are on aca6: /gis/rio/test2
This has been created via a tool called cellfilter, which is run using a config file /gis/rio/conf/test2:
XtraFile=../xtra/sat InputDir=/gis/rio/raw CellFName=detail OutputPath=../test2 OvName=overlay OvItemName=sat OvType=456 NonActiveFit=0 OutputDataFile=data OutputCellPath=data CellType=truec Rows=1559 Cols=3020 XMin=455950 YMin=3973060 XMax=456950 YMax=3973580 SwapY=n NoData=-1Both the xtra-file and the cell file are in binary format. description of those.
The cell file ( /gis/malta/raw/detail ) uses 4 Bytes per pixel since Rows*Cols*4 = 1559*3020*4=18832720 matches the size of the file. This does not use a header, just plain r,g,b + another "functional" value.
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