This local page will continue for the time being

imgCIF / CBF is an initative to extend the International Union of Crystallography CIF (Crystallographic Information File) concept to cover efficient storage of 2-D area detector data, and other large datasets.

Information on CIF may be found at http://www.iucr.org/iucr-top/cif/home.html or a number of links to different CIF projects are available. The imgCIF / CBF group are working closely with the COMCIFS committee to ensure that CBF does not diverge from CIF.

Efficient storage of large images requires binary storage so a CIF format cannot be used directly. Thus, the "Crystallographic Binary File" (CBF) format is proposed. This contains both pseudo-ASCII header sections which contain CIF data names and values, and binary sections which contain image and other data in binary formats described in the headers. Because of the binary nature of the file, the "line separators" used in the pseudo-ASCII section are always the pair of ASCII characters carriage-return, line-feed regardless of the operating system on which the file is created or tranferred. The current draft version of the CBF format is available.

Much of the work of the group and many of its members are also part of the macromolecular CIF (mmCIF) group.. For the mmCIF home page is http://ndbserver.rutgers.edu/NDB/mmcif/index.html.

The format continues to be developed from e-mail discussions held by the imgCIF group. A list server is run by John Skinner and Bob Sweet at the Brookhaven National Laboratory. To subscribe to the group send an e-mail to listproc@bnl.gov with the body containing:

subscribe imgCIF-l name@address

A message should be automatically returned explaining use of the server. Having subscribed, messages may be send to imgcif-l@bnl.gov.

Details of the Brookhaven workshop and established working groups may be found at http://ndbserver.rutgers.edu/mmcif/cbf/

A web "paper" on CBF and in particular the proposed data compression methods is under construction.

CIF is copyrighted by the IUCr and it is intended that CBF would eventually be treated in the same manner. The copyright protects the usage of the format for the whole community whilst allowing free usage. See the IUCr official statement of policy on the use of CIF/STAR.

This page has been produced by Andy Hammersley (E-mail: hammersley@esrf.fr). It is subject to further modification. If you have helpful suggestions, please send them to me. (Information on this web page.)

Some Examples of Image Data