Sustainability of Digital Formats
Planning for Library of Congress Collections
Sustainability of Digital Formats
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| Introduction | Sustainability Factors | Content Categories | Format Descriptions | Contact | |
| Full name | ISO/IEC 15444-1:2000. Information technology -- JPEG 2000 image coding system -- Part 1: Core coding system, Annex I: JP2 file format syntax (formal name) JPEG 2000 jp2 file format (common name) |
| Description | Wrapper developed by the Joint Photographic Experts Group (JPEG) for still images using JPEG 2000 core encoding. Its role (although not its extended capabilities) has been compared to that played by JFIF for JPG_DCT (JPEG encoding). The extended capabilities of JP2 grow out of its object-based design and its ability to wrap object types beyond JPEG 2000 core bitstreams, e.g., auxiliary opacity/transparency channels, color profile information, and other metadata. See Notes below for additional information. |
| Production phase | May be used for content in initial, middle, and final states. |
| Relationship to other formats | |
| Has subtype | JP2_J2K_C_LL, JP2 File Format with JPEG 2000 Core Coding, Lossless |
| Has subtype | JP2_J2K_C_LSY, JP2 File Format with JPEG 2000 Core Coding, Lossy |
| Has subtype | JP2_J2K_C_Profile_0, JP2 File with Profile 0 for JPEG 2000 Part 1, Core Coding |
| Has subtype | JP2_J2K_C_Profile_1, JP2 File with Profile 1 for JPEG 2000 Part 1, Core Coding |
| Has subtype | JP2_J2K_C_Profile_3, JP2 File with Profile 3 for JPEG 2000 Part 1, Core Coding |
| Has subtype | JP2_J2K_C_Profile_4, JP2 File with Profile 4 for JPEG 2000 Part 1, Core Coding |
| Has subtype | JP2_J2K_C_BIIF_01_00, JP2 File with BIIF Profile for JPEG 2000 Part 1, Core Coding, Version 01.00 |
| Has subtype | JP2_J2K_C_NDNP, JP2 File with NDNP Profile for JPEG 2000 Part 1, Core Coding |
| LC experience or existing holdings | JP2_FF files with lossy compression are being used for the service images of maps in American Memory; JPEG 2000 files have replaced the MrSID files used formerly to provide zoom capabilities for large images. Meanwhile, the Library and the National Endowment for the Humanities have specified JP2_J2K_C_NDNP for use as lossy-compressed service images in the National Digital Newspaper Program, which was launched during 2004. In another activity, plans are being made to prototype video reformatting in the Library's Motion Picture, Broadcasting, and Recorded Sound Division. Individual frame images will be encoded with lossless J2K_C_LL. Details are not final as of December 2006. |
| LC preference | The preceding indicates a preference for JPEG 2000 for service images. As adoption and implementation increases in other sectors, the use of the format for the Library's master images may become more and more appealing. |
| Disclosure | Open standard. Developed by Joint Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information in collaboration with ITU-T. |
| Documentation | ISO/IEC 15444-1:2000. Information technology -- JPEG 2000 image coding system -- Part 1: Core coding system, Annex I: JP2 file format syntax. See complete list of ISO/IEC JPEG 2000 documents in Format specifications below. |
| Adoption | Implementations of JPEG 2000 have been increasing steadily during 2005 and 2006. Michael Gormish, as part of his Gormish Notes on JPEG2000, now maintains a small "wiki" for his tracking of JPEG2000 adoption [http://www.crc.ricoh.com/~gormish/jpeg2000adoption.html], rather than a single page, because developments to record are increasingly frequent.
Most image manipulation programs and software libraries can now read and write JP2 files. JPEG2000 encoder chips are available, e.g., from Analog Devices and ALMA Technologies. Software encoders designed for general DSP (digital signal processing) chips are available from other manufacturers, e.g., Texas Instruments. Examples of significant adoption of JPEG2000 in commercial or government application sectors include: the Digital Cinema Initiative (see Digital Cinema Initiative Package (DCP), Version 1.0); use by the High Resolution Imaging Science Experiment (HiRISE) flying on board NASA's MARS Reconnaissance Orbiter mission; and use in the stock photography service AbsolutVision. Use of JPEG 2000 in medical and geospatial imaging applications is growing steadily. For example, in late 2006, lossless JPEG 2000 was proposed as the standard for compressed imagery in the Western Australia Land Information System in a report that considers adoption in GIS communitities in some detail. Security cameras that use JPEG2000 for compression are on the market, e.g., from Sanyo. Another specialist camera system with built-in JPEG2000, from Air Resource Specialists, Inc. is for monitoring air-quality. Many cultural heritage institutions, including the Library of Congress, that had used MrSID to support zoom views of large images such as maps, have migrated to using JPEG 2000 as a service format. Minutes of the ALA/LITA JPEG2000 Interest Group meeting in June 2006 indicated usage by several participants: Western Michigan University is using JPEG2000 for access to digitized manuscripts; LexisNexis is using JPEG2000 in the maps portion of the U.S. Serials Set digitization program; the Smithsonian Libraries has started converting archival TIFFs to JPEG2000 and is considering use of the standard in the Biodiversity Heritage Library project. There was also discussion of the state of support for JPEG2000 in software systems used by libraries. Insight (Luna), ContentDM (DiMeMa), and Digitool (Ex Libris) can now use JPEG2000 and have deployed server-side transformation to deliver an image to the user within a regular web-browser. In early 2007, some commentators on the Web called attention to the fact that JPEG 2000 encoding is not being built into camera chips nor is JPEG 2000 decoding native to Web browsers. This has led them to compare the adoption of the format in unfavorable terms to JPEG_DCT, the earlier JPEG codec, which is native to virtually all digital cameras and browsers. Earlier indications of adoption were: The Guide to the Practical Implementation of JPEG 2000 (2003, see Useful references below), reports that "Some of the aerial photography on the street-mapping web site MapQuest.com is provided by a JPEG 2000 back-end system, chosen for its ability to extract small regions from very large images at high speed. Yahoo! Messenger, an instant-messaging client with video capabilities, also uses JPEG 2000, to achieve high compression and hence higher resolution and frame-rate. In both cases, the use of JPEG 2000 is not typically manifest to the end-user." See also Peter Murray's presentation Adoption of JPEG 2000 by Libraries and Archives. |
| Licensing and patent claims | Licensing is associated with the encoding; see J2K_C. |
| Transparency | See J2K_C |
| Self-documentation | A small set of metadata is required: basic image data (height, width, number of components, bit-depth); color specification (see notes on color maintenance below), and a flag indicating the presence or absence of intellectual property information. This may be supplemented by optional information, e.g., capture or dispay resolution (relating pixel size to physical size) and by data presented in three optional boxes: (1) a box for XML data (specific recommendations regarding XML are provided in Part 2 of the standard and pertain to JPX but may be used in JP2 as well), (2) an IPR box (see technical protection considerations just below), and (3) a UUID box which provides for an object identifier or identifier-references to other digital objects (described by one commentator as providing a generic mechanism for extending the file format to include application-specific data). |
| External dependencies | None |
| Technical protection considerations | Like the rest of the members of the JPEG 2000 file format family, JP2_FF provides an IPR box for rights management information that may be used as inputs to access management systems. |
| Normal rendering | Good support |
| Clarity (support for high image resolution) | See J2K_C |
| Color maintenance | Rich support, further extended in JPX. In JP2_FF, the color space of the decompressed image data is indicated in the Color Specification box inside the JP2 Header box, which contains the ICC profile when applicable. If the color spaces sRGB, sYCC, or the defined greyscale space are used, this is indicated by a number. For palettized images, the Palette box holds the look-up table and the Component Mapping box defines which codestream components map to which palette components or bypass the palette. The resulting components are called ‘channels’ in the standard to distinguish them from the initial codestream components. Finally, the Channel Definition box maps codestream components (if unpalettized) or channels to color components, allowing them to be permuted if desired and enabling support for ‘alphachannels’ (opacity) as well as color channels. Note that J2K_C provides information about actual color encoding. |
| Support for graphic effects and typography | No support for vector graphics. |
| Functionality beyond normal rendering | The JPEG 2000 family offers many extended functionalities, some of which grow out of the options of scalability offered by the various encodings, and which extend to the interactivity provided by JPIP, destined to be Part 9 of the JPEG 2000 standard; see JPIP-Architecture-VCIP2003.pdf |
| Tag type | Value | Note |
| Filename Extension | jp2 | |
| Internet Media Type |
image/jp2 image/jpeg2000 image/jpeg2000-image image/x-jpeg2000-image |
From the File Extension Source; the first MIME is also provided by http://www.rfc-editor.org/rfc/rfc3745.txt |
| Magic numbers | Hex: 00 00 00 0C 6A 50 20 20 0D 0A 87 0A 00 00 00 14 66 74 79 70 6A 70 32 | From the File Extension Source; the official specification (pp. 151-54) explains that this string includes the Signature Box identifier and contents and the File Type Box identifier. |
| File type brand | jp2\040 [jp2 plus the space character] | Value in the File Type Box, which is similar to the ISO_BMFF file type box. |
| Macintosh type code | jp2\040 [jp2 plus the space character] | As specified by Annex I.2.1 of the specification. |
| General | The JPEG 2000 file format family includes: • JP2_FF, JPEG 2000 Part 1 (Core) jp2 File Format (this document) • JPX_FF, JPEG 2000 Part 2 (Extensions) jpf (jpx) File Format • JPM_FF, JPEG 2000 Part 6 (Compound) jpm File Format The family is descended from QuickTime. This lineage is shared with ISO_BMFF and its offshoots, which include MP4_FF_2, MP4_FF_AVCE, and MJ2_FF, itself a wrapper for JPEG 2000 core-encoded images that represent sets of film or video frames. From Guide to the Practical Implementation of JPEG 2000, cited in Useful references below: "JP2 was designed to be inherently extensible. The extended file formats that are defined in later parts of the standard all incorporate a degree of backwards-compatibility with JP2: for each extended format it is possible to construct extended files that also conform to JP2. (A JP2 reader would ignore any extensions that it did not understand.) Thus, the definition of JP2 in Part 1 can also be considered an implicit definition of an architecture known informally as the ‘JP family’. . . . A JP family file is a sequence of ‘boxes’. [These are called atoms in the QuickTime specification. -- ed] A box consists of a 4-byte length field followed by a 4-byte type field followed by the content of the box. The content is defined for each box type and may include boxes. A box whose content consists only of boxes is called a superbox. There are two special values of the length field. A value of zero means that the box extends to the end of the file. A value of 1 means that the true length of the box follows the type field (before the content) in an 8-byte extended length field; this permits boxes up to (264 – 1) bytes in length. The length includes the whole box from the start of the length field to the end of the content." |
| History |
URLs
Print
The file format described on this page is specified in Annex I of Part 1 of the standard, i.e., the first citation in the following list. For reference, this listing includes the other parts, insofar as they are publicly available from ISO in December 2004.
URLs
• http://www.jpeg.org/jpeg2000/
• Gormish Notes on JPEG 2000 (http://www.crc.ricoh.com/~gormish/jpeg2000.html)
• Gormish Notes on Adoption of JPEG 2000 (http://www.crc.ricoh.com/~gormish/jpeg2000adoption.html)
• Annotated list of URLs for JPEG 2000 information (http://datacompression.info/JPEG2000.shtml)
• Compression Links Info: JPEG 2000 Area (http://www.compression-links.info/JPEG2000)
• MIME types for JPEG 2000 (http://www.rfc-editor.org/rfc/rfc3745.txt)
• Data Compression News Blog: JPEG2000 (http://www.c10n.info/?s=jpeg2000)
• Adoption of JPEG 2000 by Libraries and Archives by Peter Murray (http://www.cni.org/tfms/2004b.fall/abstracts/PB-adoption-murray.html).
• Minutes of the ALA/LITA JPEG2000 Interest Group meeting in June 2006 (http://dltj.org/2006/06/j2kig-minutes/)
• JPIP-Architecture-VCIP2003.pdf (http://www.ee.unsw.edu.au/~taubman/publications_files/JPIP-architecture-vcip03.pdf)
• National Digital Newspaper Program, project Web site. (http://www.loc.gov/ndnp/).
• Technical guidelines for the National Digital Newspaper Program (http://www.loc.gov/ndnp/pdf/ndnp_techguide.pdf).
• Report
for Western Australian Department of Land Information (RFQ DLI 084/2006) on results of investigation of
JPEG 2000 imagery for operational & archive storage requirements (http://www.walis.wa.gov.au/projects_and_activities/JPEG2000/JP2K_Report_for_DLI_v1.0.pdf)
• High Resolution Imaging Science Experiment: JPEG2000 FAQ for the National Digital Newspaper Program (http://hiroc.lpl.arizona.edu/images/jp2.html).
• Imaging SDK from Pegasus aimed at medical imaging applications (http://www.pegasusimaging.com/picmedx.htm).
• AbsolutVision, a stock photo agency (http://www.absolutvision.com/).
Print
• Colyer, Greg and Richard Clark. Guide to the Practical Implementation of JPEG 2000. London: British Standards Institute, 2003. ISBN: 0580412423 BSI: PD 6777:2003. Available as PDF file; link to point-of-sale at http://www.jpeg.org/jpeg2000/index.html.
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