Vector Feature Extraction from Topographic Maps &
Digitizing features is one of the most time consuming
and tedious aspect of compiling GIS data, but also one of the most vital
ingredients in creating your GIS database. LAND INFO saves you from
this grueling task and allows you to better invest your efforts in other
LAND INFO extracts vector features from topographic maps, satellite imagery, and aerial photography. Topo maps are an ideal base for large-area coverage, and can optionally be updated with detailed coverage extracted from aerial or satellite imagery of select areas. Because topographic maps often include ground truthing they may supply detail above and beyond satellite imagery, as an example cultivated areas can clearly be distinguished in satellite imagery but topographic maps may show the specific crop being grown (on the other hand the satellite imagery is much more current that the topographic map.)
Available layers, depending on map scale/publisher, include:
• Spot Height
Each layer is output in a vector file format, enabling
easy integration with original imagery, maps and other geo-data. LAND
INFO also offers feature extraction from satellite imagery. Contact
us today for more information.
|What are some
common uses for Vectors?
• Base Mapping
• Military Applications
• Telecommunication Modeling
• Simulation & Training – Military, Aviation,
• Cartography & Map Publishing
|Advantages of using LAND
INFO Vector Features:
• Accuracy and Quality - Extensive quality control
• Extensive Geographic Coverage - Utilizing our worldwide Topographic
• Quick Turn-around Times - we will help you meet your deadlines
• Affordable - You'll be surprised how much money LAND INFO will save
you, not to mention the headaches of data conversion.
• Custom recommendation for your specific project area/type
LAND INFO uses both automatic and manual methods of extraction. The automatic method uses pixel value interpretation software to trace a vector line over continuous pixels of certain color values. The manual method consists of heads-up/on-screen digitizing over a DRG (Digital Raster Graphic – geo-referenced color scan of a topographic map or nautical chart)
Once the vector features are extracted to line
files, they can be attributed to your project specifications. This includes
having a separate vector file for every vector feature or combining
many vector features into one vector file with appropriate attribution.
Specific attribution, such as codes and numeric representation, can
be added to the vector files attribution table to easily ingest the
data into specific applications.
• Esri .shp shapefile or .mdb GeoDatabase
• AutoCAD .dwg or .dxf
• MapInfo MIF/MID/TAB
• Microstation .dgn
(Note:If your desired output is not listed
above we can easily convert to proprietary formats.)
LAND INFO provides several different delivery
• USB flash drive
• External hard drive (USB 2.0/USB 3.0/FireWire 400/FireWire 800/eSata)
Vector Feature Extraction has several areas that need to be checked to assure a quality GIS Data product. This includes accurate digitization from the source material, built topology, and attribution accuracy.
- The source material is used as a benchmark to ensure
that all derived data is accurately captured.
- All vector files are overlaid on top of their source
material and visually inspected by trained technicians to assure that
all features are captured accurately.
- The attributes are verified against the source
data and against any client data that is provided to ensure its smooth
incorporation into client applications.
Scales for the Vector Feature extraction will replicate
the scale of the map for which the features were derived.