Sustainability of Digital Formats
 Planning for Library of Congress Collections

Format Description Categories >> Browse Alphabetical List>> Back

Identification and description

Full name	TIFF Bitmap with LZW Compression
Description	A tag-based file format for storing and interchanging raster images; in this subtype, TIFF wraps a bitmap compressed using LZW (Lempel-Ziv-Welch Compression Encoding).
Production phase	Most often an initial-state or middle-state format; may serve as final-state format.
Relationship to other formats
Subtype of	TIFF_6, TIFF, Revision 6.0 and earlier
Contains	LZW, LZW Compression Encoding

Local use

LC experience or existing holdings	See TIFF_6
LC preference	TIFF is one of the preferred formats for bitmapped images, although TIFF_UNC and TIFF_G4 are preferred to TIFF_LZW.

Sustainability factors

Disclosure	See TIFF_6
Documentation	See TIFF_6
Adoption	TIFF_LZW has seen some use in digital library projects but has not been as widely deployed as TIFF_UNC and TIFF_G4. TIFF_LZW is listed but not preferred for raster images in the list of FCLA recommended formats (Florida Center for Library Automation; www.fcla.edu/digitalArchive/pdfs/recFormats.pdf).
Licensing and patents	See LZW
Transparency	See LZW
Self-documentation	See TIFF_6
External dependencies	None
Technical protection considerations	None

Quality and functionality factors

Still Image
Normal rendering	Good support.
Clarity (high image resolution)	See TIFF_6.
Color maintenance	See TIFF_6
Support for graphic effects and typography	See TIFF_6
Functionality beyond normal rendering	See TIFF_6

File type signifiers

Tag	Value	Note
Filename extension	See related format.	See TIFF_6
Internet Media Type	See related format.	See TIFF_6
Magic numbers	See related format.	See TIFF_6

Notes

General
History

Format specifications

• See TIFF_6

Useful references

URLs

• See TIFF_6