Many GIS programs are based on vector technology. These are the
most complex methods because there are many ways to save coordinates,
attributes, data structure and visualisation information.
||ESRI Generate Line
||Simple ASCII format which can handle point and line data.
||MicroStation Design Files
||DGN is an intern format for MicroStation, a CAD program (CAD means
“Computer-Aided Design”). This format is well documented
and standardised, which makes it possible to use it an import/export
format. DGN files contain detailed visualisation information (display).
||DLG is used by the US Geological Survey (USGS) for handling vector
information from printed paper maps. It contains very precise coordinate
information and sophisticated information about object classification,
but no other attributes. DLG does not contain any visualisation information
(display). This format is mainly used by the USGS and other American
agencies, which have used it for publication of many digital maps.
||Autodesk Drawing Files
||DWG is an intern format for AutoCAD. AutoCAD can convert DWG files
to DXF files without loosing graphic information. There are many possibilities
for saving attribute data in DWG files. A common standard method uses
Extended Entity Data (EED) to link attributes, but other methods are
possible. Because of the lack of standards for linking attributes,
problems may occur while converting this format between systems.
Drawing eXchange Format
||DXF is a common transfer format for vector data. It contains visualisation
information and is supported by nearly all graphic programs. There
are many ways for saving attribute data in DXF format and to link
DXF objects to external attributes (see DWG above). Nearly all programs
can successfully import this format because of high standards.
||E00 is a transfer format available both as ASCII and binary form.
It is mainly used to exchange files between different versions of
ARC/INFO, but can also be read by many other GIS programs. It is a
common format for GIS data found on the Internet.
||XML-standard for exchanging and saving geographical vector data.
It is used in the Open GIS Consortium.
|Is a format, which can handle point, line and polygon data, as well
as text and symbols. But it is not possible to convert and exchange
||MIF/MID is MapInfo’s standard format, but most other GIS programs
can also read it. The format handles three types of information: geometry
attributes and visualisation.
Data Transfer System
SDTS is a transfer format developed in the USA and is designed
for handling all types of geographical data. SDTS can be saves as
ASCII or binary. In principle, all geographical objects can be saved
as SDTS, including coordinates, complex attributes and visualisation
information. These advantages nevertheless increase complexity.
To simplify it, many standards have been developed as “co-projects”
to SDTS. The first of these standards is Topological Vector Profile
(TVP), used to save some types of vector data.
||Shape is ArcView’s internal format for vector data. Associated
to the Shape file (*.shp), there is a file to handle attributes (*.dbf)
and an index file (*.shx). Nearly all other GIS programs can import
||XML-standard for presentation of vector on the Internet. It is approved
in the World Wide Web Consortium.
Integrated Geographic Encoding and Referencing Files
||TIGER is an ASCII transfer format made by the US Census Bureau to
save road maps. It contains complete geographic coordinates and is
line-based. The most important attributes include road names and address
information. TIGER has its own visualisation information.
||VPF is a binary format made by the US Defense Mapping Agency. It
is well documented and can easily be used internally or as a transfer
format It contains geometry and attribute information, but no visualisation
information. VPF files are also named VMAP product. The Digital Chart
of the World (DCW) is published in this form.
||Idrisi32 ASCII vector export format
||IDRISI 32’s vector export format (ASCII).
||Microsoft Windows Metafile
||WMF is a vector file format for Microsoft Windows Operation Systems.
WMF files are actually a compilation of GDI (Graphics Device Interface).
Raster files are used generally to save images, like for example,
a scanned paper map, digital photographs or satellite images, but
also to save variables which continuously vary in space, like topography
and temperature. Images from satellites, or other aircrafts, are
known as remote sensing data. The resolution of the remote sensing
data and scanned maps refers to the area on the ground covered by
one pixel. This differs to other image data, where the resolution
is given in dots per inch (dpi).
||Arc Digitized Raster Graphics
||ADRG is a format created by the US military to save paper maps in
||Band Interleaved by Line
||BIL is a computer compatible tape (CCT) format that stores all bands
of remotely sensed data in one image file. Scanlines are sequenced
by interleaving all image bands. The CCT header appears once in a
||Band Interleaved by Pixel
||When using the BIP image format, each line of an image is stored
sequentially, line 1 all bands, line 2 all bands, etc. For example,
the first line of a three-band image would be stored as p1b1, p1b2,
p1b3, p2b1, p2b2, p2b3, where p1b1 indicates pixel one, band one,
p1b2 indicates pixel one, band two, etc.
||BSQ is a computer compatible t ape (CCT) format that stores each
band of satellite data in one image file for all scanlines in the
imagery array. The CCT headers are recorded on each band.
||DEM is a raster format created by the USGS (US Geological Survey)
for saving elevation data. In contrast to other raster formats where
the cell values represent the colour intensity, the cell values in
DEM represent the elevation for that position on the Earth’s
||ArcINFO:s (ESRI) elevation data format.
30 Arc Second Elevation Data Set
GTOPO30 is a global, digital elevation model with a horizontal
cell size of approx. 1km (30 seconds). GTOPO30 was created from
different raster and vector sources.
||GeoTIFF is a form of TIFF (Tag Image File Format) format for georeferenced
||GRIB is the World Meteorological Organisation’s (WMO) standard
for grid-based meteorological data.
||PC Paintbrush Exchange
||PCX is a common raster format found in many scanners and graphic
||Spatial Data Transfer Standard
||SDTS is a format for transferring geographical information. A SDTS
variant is specifically made for transferring raster data.
||Tagged Image File Format
||Like PCX, TIFF is a common raster format produced by drawing programs
and scanners. TIFF format gives a relatively big data file, but compresses
the data without loss of information.
Data Format Information FAQ
Data Formats - GeoCommunity