Sustainability of Digital Formats: Planning for Library of Congress Collections
Sustainability of Digital Formats: Planning for Library of Congress Collections |
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| Introduction | Sustainability Factors | Content Categories | Format Descriptions | Contact | |
| Full name | MapInfo dataset format |
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| Description |
Sometimes called the MapInfo Native format or the MapInfo TAB format, the MapInfo dataset format is a proprietary format developed for use with MapInfo software products. A MapInfo dataset consists of a number of physical files. Two files are required for textual and numeric data without graphic objects. The table structure in ASCII format ( *.TAB ) is the main file for a MapInfo table. The .TAB ASCII file is the link between all other files and holds information about the type of data file. The attribute data (*.DAT) is stored in binary format. These two files support a "browser" view of the tabular data, a view comparable to a spreadsheet. To display geographic information (the graphic representation of data in vector form) in Mapinfo Professional, using the "mapper" view, two additional files are required. Map objects are stored in binary format and represented in a *.MAP file. Graphic data is linked to database information in a file (*.ID) that contains a 4-byte integer index into the MAP file for each feature. A fifth file, in binary format, (*.IND) is present if any fields are indexed and serves as an index to the MapInfo tabular (*.DAT) file. The format is sometimes described as TAB/MAP. MapInfo software creates temporary files as work is in progress; see Notes. |
| Production phase | Primarily initial state and middle state use. |
| Relationship to other formats | |
| Must have component | The mandatory TAB file, with extension .tab, for a MapInfo dataset. The .tab file is an ASCII text file describing the structure of the dataset and its .DAT file. The .tab file is not described separately on this website. |
| May have component | MapInfo_DAT, MapInfo Data File (DAT). Most MapInfo datasets have a .dat file in the DBF format, particularly those distributed as a public resource. However, MapInfo native datasets may use other formats to hold the raw data, including Excel spreadsheets. See Notes. |
| May have component | Optional files in a MapInfo dataset are the .map file, the .id file, and the .ind file. These files are not described separately on this website at this time. |
| Affinity to | MapInfo MIF/MID (MapInfo Interchange Format). MapInfo datasets can be transformed into the the MIF/MID format, not described at this time. |
| LC experience or existing holdings | |
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| LC preference |
| Disclosure | The MapInfo format is developed and regulated by Pitney Bowes Business Insight (formerly known as Pitney Bowes MapInfo and Group 1 Software) as a proprietary format. |
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| Documentation | No complete specification is available for the MapInfo format. A March 2000 article in Spatial News, Notes on the MapInfo® Native table format, provides useful information on the format. MapInfo Products KnowledgeBase includes an annotated excerpt of a sample .tab file, the mandatory component file that describes a MapInfo dataset, at Contents of a MapInfo *.tab file. |
| Adoption |
Open source software is available for reading and writing MapInfo datasets in the MapInfo Native (TAB/MAP) format and the MapInfo Interchange Format. Geospatial Data Abstraction Library (GDAL/OGR) is a cross platform C++ translator library for raster (GDAL) and vector (OGR) geospatial data formats that is released under an X/MIT style Open Source license by the Open Source Geospatial Foundation. The MapInfo dataset formats are supported in OGR. The MITAB software library and utilities make use of the OGR software to provide a tool specifically for MapInfo datasets. MapInfo solutions are available in 21 languages in 60 countries. The USGS Digital Data Viewer: dlgv32 Pro, a limited-feature version of commercial software Global Mapper, originally from the U.S. Geological Survey (USGS), can import and export data to the MapInfo MIF/MID (MapInfo Interchange Format) and TAB/MAP formats. MapInfo Pro implements OGC's Web Map Service (WMS) and Geography Markup Language (GML) specifications. Pitney Bowes' Envinsa and MapExtreme products are OGC WMS compliant. |
| Licensing and patents | MapInfo is a registered trademark of MapInfo Corporation. |
| Transparency | The .tab file is an ASCII text file and thus readable with basic editing tools. See DBF for information on the transparency of dBASE Table Files. |
| Self-documentation | The .tab file can contain a metadata section. |
| External dependencies | TBD |
| Technical protection considerations | TBD |
| Dataset | |
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| Normal functionality | The .DAT file which contains the attribute data allows numbers to be stored in a variety of ways: binary integers occupying 1,2,4, or 8 bytes; binary floating point numbers in single precision (4 bytes) or double precision (8 bytes); and "decimal"numbers as ASCII strings. In practice, the most commonly used numeric formats are 2- and 4-byte integers and double-precision floating point. See Guidance notes on Native MapInfo Format from By Design, for a discussion of numeric formats and precision in MapInfo. |
| GIS images and datasets | |
| Normal functionality | The MapInfo dataset format is designed to support browsing of tabular data and display of such as a layer on a map based on geospatial referencing stored in the dataset. |
| Support for GIS metadata | In the .tab file, a metadata section can be included. This section describes properties of the table/map. Some of the items that can be included here are projection settings, map bounds, source of data, vintage of data, object types, etc. There is no standard set of properties contained in this section. Some operations by MapInfo software will add metadata to this section. |
| Other | |
| Tag | Value | Note |
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| Filename extension | tab |
The *.tab file is the main file in the group. |
| Tag | Value | Note |
| Filename extension | dat |
For the MapInfo tabular file in dBase format |
| Filename extension | id |
For the database information file |
| Filename extension | map |
For the map object file |
| Filename extension | ind |
For the index file |
| General |
The MapInfo Professional User Guide includes a brief description of the component files in a MapInfo table, which is summarized here. All MapInfo Professional tables have the following two files:
If a table has graphic objects, there are two more files associated with the table:
A table may also include an index file:
Temporary files are created by MapInfo while there are edits on MapInfo files. Those are:
When using a remote table such as Oracle Locator or Spatial, if the data is downloaded to the local machine, the temporary file extensions are:
MITAB is an Open Source C++ library to read and write MapInfo TAB (binary) and MapInfo Interchange (MIF/MID) files. MITAB is based on the OGR library which is an implementation of the Open GIS Consortium Simple Features specifications for OLE/COM and CORBA. |
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| History | MapInfo was founded in 1986 by Laszlo Bardos, Andrew Dressel, John Haller, Mike Marvin, and Sean O’Sullivan. The company originated as a Rensselaer Polytechnic Institute (RPI) incubator project. The original name was Navigational Technologies Incorporated (NTI), and the first intended product was for in-car navigation. MapInfo held an initial public offering (IPO) in 1994. On April 19, 2007 Pitney Bowes entered into a merger agreement to acquire MapInfo Corporation for approximately $408 million in cash. Following the acquisition, MapInfo has changed its name to Pitney Bowes MapInfo Corporation. As of January 28, 2009, MapInfo and Group 1 Software are operating as one division called Pitney Bowes Business Insight. |
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