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Compression Formats

Contents 1 Background 2 Compression Formats and Software 3 Concatenation Formats and Software 4 Additional Resources 5 Subsections of this Article 6 Information about this article 7 Contact

Background

These formats are used for efficient storage or transmission of data, using a variety of compression algorithms in software programs that range from open-source to commercial. The excellent resource link below covers the subject very thoroughly. We include here also two formats that do not actually reduce data volume, but are used for transmission of multiple files concatenated to a single file, so in effect they reduce transmission overhead.

Compression Formats and Software

This table summarizes the most important formats/software encountered often in marine work.

Format Name	Associated Software	Documentation	Comments
Zip (ZIP)	WinZip, among at least a dozen others; Microsoft and Apple include built-in Zip support	Wikipedia: ZIP (file format) WinZip Homepage	Some GIS programs can work directly from the Zip files, performing the decompression automatically This is the actual format used for KMZ files, so the extension should be changed back to ZIP in order to inspect the file contents.
Gzip (GZ)	gzip	Wikipedia: gzip Gzip Homepage	Ocean Data View must work directly from the gz versions of World Ocean Database files, so they should not be unzipped beforehand
Bzip (BZ2)	Bzip2	Wikipedia: Bzip2 Bzip Homepage	Commonly used by US NASA for data file distribution

Concatenation Formats and Software

This table summarizes the most important formats/software encountered often in marine work.

Format Name	Associated Software	Documentation	Comments
TAR (*.tar)	tar (UNIX utility)	Wikipedia: Tar file	Tar files can also be zipped after concatenation, so *.tar.zip and *.tar.gz files are often encountered, called "tar balls".  Most commercial de-compression programs can handle these.
E00 (*.e00)	ArcGIS and some other GIS programs Import71 - Free utility from ESRI	Geocommunity: Working with E00 Data Export (E00) Format Analysis Updated Version of the E00 Analysis	ESRI shapefile and coverage file "interchange" format.  Contains any of about 15 different specifically formatted types of geographic data, strung together much like a tar file.  Import71 converts the file to either a shapefile or a coverage.

Additional Resources

• Wikipedia: Data compression

Subsections of this Article

No subsections available

Information about this article

Short title: Compression Formats

Description: These formats are used for efficient storage or transmission of data, using a variety of compression algorithms in software programs that range from open-source to commercial.

Expertise level: beginner

Author: Murray.Brown

Approval status: approved

Approved by: Murray.Brown

Last change: 2011-12-2

Subsection of: Marine Data Format Types

Contact

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