2.3. Specification of the Crystallographic Binary File (CBF/imgCIF)
H. J. Bernstein and A. P. Hammersley
Abstract
The Crystallographic Binary File (CBF) is an electronic file supporting the efficient storage of large quantities of experimental data in a self-describing binary format. Its primary function is to handle large image data sets within laboratories and for interchange between collaborating groups. Except for embedded binary data segments, the format is derived from that of the pure-ASCII Crystallographic Information File (CIF), so that all suitable CIF data items describing the crystallographic experiment and any structural results may be included. Embedding of binary data fields makes use of Internet standard MIME headers to facilitate identification and handling of separate binary components.
Where file size or efficiency of processing are not important, the embedded binary data may be ASCII-encoded according to a specified protocol. The resultant file, containing only ASCII character data, is fully compatible with CIF and is known as an image-supporting crystallographic information file (imgCIF).
This chapter describes in detail the structure and format of CBF and imgCIF representations, and explains how to convert from one format to the other.
Links
Dictionaries
The following dictionary is referenced in this chapter:
Specifications
Chapter 2.3 of this volume should be considered the definitive specification for the Crystallographic Binary File and its imgCIF isomorph (CBF/imgCIF) and should be cited as:
Bernstein, H. J. & Hammersley, A P. (2005). International Tables for Crystallography, Volume G, Definition and exchange of crystallographic data, edited by S. R. Hall & B. McMahon, Chapter 2.3, Specification of the Crystallographic Binary File (CBF/imgCIF). Heidelberg: Springer.
Some drafts of historical interest are provided as Supplementary documents (see below).
See also
Supplementary documents
The following historical documents may be of interest:
References
Freed, N. & Borenstein, N. (1996a). Multipurpose Internet Mail Extensions (MIME) part five: Conformance criteria and examples. RFC 2049. Network Working Group. http://www.ietf.org/rfc/rfc2049.txt.
Freed, N. & Borenstein, N. (1996b). Multipurpose Internet Mail Extensions (MIME) part one: Format of Internet message bodies. RFC 2045. Network Working Group. http://www.ietf.org/rfc/rfc2045.txt.
Freed, N. & Borenstein, N. (1996c). Multipurpose Internet Mail Extensions (MIME) part two: media types. RFC 2046. Network Working Group. http://www.ietf.org/rfc/rfc2046.txt.
Freed, N., Klensin, J. & Postel, J. (1996). Multipurpose Internet Mail Extensions (MIME) part four: Registration procedures. RFC 2048. Network Working Group. http://www.ietf.org/rfc/rfc2048.txt.
Hall, S. R., Allen, F. H. &
Brown, I. D. (1991). The Crystallographic Information File
(CIF): a new standard archive file for crystallography.
Acta Cryst. A47, 655-685.
See also
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![[cdrom]](../graphics/cd.gif){kind=small}
HTML version
(http://www.iucr.org/iucr-top/cif/standard/cifstd1.html).
IEEE (1985). IEEE Standard for binary
floating-point arithmetic. ANSI/IEEE Std 754-1985. New York:
The Institute of Electrical and Electronics Engineers, Inc.
See also http://en.wikipedia.org/wiki/IEEE_754.
Moore, K. (1996). MIME (Multipurpose Internet Mail Extensions) part three: Message header extensions for non-ASCII text. RFC 2047. Network Working Group. http://www.ietf.org/rfc/rfc2047.txt.
Rivest, R. (1992). The MD5 message-digest algorithm. RFC 1321. Network Working Group. http://www.ietf.org/rfc/rfc1321.txt.