Synergising Open Data Standards & NRIS Standards : A Case Study - Coverage to Shapefile
Navita J Thakkar
Space Applications Centre
India
Email: navita@sac.isro.org
Pushpalata B Shah
E mail:pushpa@ipdpg.gov.in
IC Matieda
E mail:matieda@ipdpg.gov.in
Abstract
Space Programe and Remote Sensingonal infrastructures is not new. The National Natural Resources Information System (NRIS) is an on-going project of Department of Space. The NRIS program has penetrated to the district level in each and every state and union territory of the country. It is providing a common, consistent infrastructure upon which a variety of government, private sector and community activities are taking place. This has been possible because of the excellent standards laid down by the project called the NRIS STANDARDS. With a view to achieve maximum economy in terms of cost, time, space and human efforts, the need for standards has been well established.
Standards for geographic information and services are currently being developed within the international standards committee ISO/TC 211 and the Open GIS Consortium. The NRIS standards in their current form are best suited for handling spatial datasets in ‘coverage’ form (ESRI e00 format). This being a proprietary format, studies were undertaken to explore methods and means to migrate to other open data formats, one of them is a Shape File. The shape file was preferred over the other formats as it is a more open standard. In order to render any map correctly a basic set of four files is required:
Shape File: (.shp) The file that stores the feature geometry.
- Shape Index File: (.shx) The file that stores the index of the feature geometry.
- dBase IV File: (.dbf) The dBase file that stores the attribute information of features.
- Projection File: (.prj) The file that stores information about the projection system of the map.
To render the various features of a map, an attribute that uniquely identifies each feature is required. The designation of such attributes for various themes has been done according to the NRIS standards, standardised and documented in the form of a Standards Document titled National (Natural) Resources Information System (NRIS) – Node Design and Standards published by the National Natural Resources Management System (NNRMS), ISRO HQs, Bangalore. We are also exploring the ways and means to switch over to Geodatabases, the latest being offered in the market. The current paper, describes
- The methodology adopted
- The software package developed to migrate to ‘shp’ file format
- The data verification package that checks the conformance of a dataset to NRIS standards
& indicates what is missing for erroneous datasets.