Format Description Categories
Browse Alphabetical List
CPC, Cartesian Perceptual Compression
Format Description Properties
- ID: fdd000007
- Short name: CPC
- Content categories:
- Format Category:
- Other facets:
unitary, binary, sampled
- Last significant FDD update:
- Draft status: Partial (low priority for LC)
Identification and description
||CPC (Cartesian Perceptual Compression)
||The CPC specification defines both a datastream and an associated file format for a compressed, raster (bit-mapped) image, designed for scanned bitonal documents. The method is based on matching of symbols. Cartesian Products claims that files are typically 5 to 20 times smaller than bitonal TIFFs. The compression ratio increases for longer documents.
||Potentially an initial-state or middle-state format for scanned documents; more often used as final-state format.
|LC experience or existing holdings
||For instances where bitonal images reflect content adequately, open standards, e.g., TIFF_G4, are preferable.
Proprietary compression scheme. Cartesian Products makes available APIs (application programming interfaces) to facilitate development of software using the scheme.
||No specification found. An overview is at http://www.cartesianinc.com/Tech/tech-overview.html
Requires plug-in or viewer for use. Various online document supply services that serve specialized audiences use CPC files for delivery, expecting recipients to download and install the plug-in or viewer.
Cartesian Inc. provides a page of clients at http://www.cartesianinc.com/General/clients.html; however, the date on this page indicates that it has not been updated since 2007.
Cartesian Inc. provides several viewers and compression tools. Viewers and decompression are free. Compression requires a purchased license after an evaluation allowance. Two APIs are available as software development kits at http://www.cartesianinc.com/Tech/API/. As of January 2014, the pages describing compression tools and viewers indicate updating in 2013 and 2014. A CPC viewer has been released for the iPad.
| Licensing and patents
||Patent filed in 1991 and issued in 1994 (#5,303,313). Treated in proprietary fashion.
Depends upon algorithms and tools for decompression to read; requires sophistication and access to documentation to build tools.
Two APIs are available as software development kits at http://www.cartesianinc.com/Tech/API/.
|Technical protection considerations
Quality and functionality factors
||Limited to bitonal images.
|Clarity (high image resolution)
||Limited to bitonal images. Intended primarily for documents.
||None. CPC is limited to bitonal images.
|Support for vector graphics, including graphic effects and typography
|Functionality beyond normal rendering
File type signifiers and format identifiers
Useful referencesURLsBooks, articles, etc.
Last Updated: Tuesday, 14-Feb-2017 13:52:17 EST