1、AIIM MS53 93 W 3032348 0500353 O76 = ANSI/AII M MS53-1993 1 - 7- - - 1 I II L- -_I I _ - mended Practice - File Format for Storage and Exchange of Images - Bi-Level Image File Format: Part 1 - 1 r- lj ! I L- - - Standard AiIM Association for Information and Image Management 1100 Wayne Avenue, Suite
2、1100 Silver Spring, Maryland 20910-5699 Telephone 301/587-8202 March 22, 1993 - - -: AIIM MS53 93 m LOL234B 0500154 TO2 m ANSVAIIM MS53-1993 Standard for t n fo r mat i o n and Image Management - Standard Recommended Practice - File Format for Storage and Exchange of Images - Bi-Level Image File For
3、mat: Part 1 Association for Information and Image Management This standard recommended practice specifies a file format for the exchange of bi-level electronic images. It addresses one bit per picture element (pel), bi-level imagery that is either compressed or not compressed and is based on the Ope
4、n Document Architecture (ODA) Raster Document Application Profile (DAP). AIIM MS53 93 m 1012348 0500155 949 m Contents Foreword 1 Scope and purpose 2 Normative references. . 3 Definitions 4 Format of variables . 5 Introduction . 6 Requirements Annexes . 1 . 1 . 1 . 2 . 3 . 3 . 7 Annex A (normative)
5、File format components . 13 Annex B (informative) ASN.1 example code . 24 Annex C (informative) Tutorial on ASN.l . 35 Annex D (informative) Uncompressed escape and Annex E (informative) Examples of possible Annex F (informative) Adding an object wrapper fill bits 39 output . 40 around All .47 Annex
6、 G (informative) Suggested reading . .48 Tables 1 Restricted variables . 4 2 3 4 Format for integer values 7 5 Format for lengths . .8 A.l Document profile 14 A.2 Document layout root. . .17 A.3 Document layout page 18 A.4 Document layout frame . 19 AS Document layout block base .20 A.5.1 A52 Docume
7、nt layout block terminator (no clipping). .21 A.5.3 Document layout block terminator (clipping) .21 A.6 Content portion base .22 A.6.1 A.6.2 Content portion definite length terminator. .22 A.6.3 Content portion indefinite length terminator . .23 F.1 All object wrapper 47 Figures 1 Example of page la
8、yout .8 2 Definition of direction . 10 3 Examples of direction . 10 4 Decision diagram for determining table usage for Annex A . i Integer variables (see Table 4 for form). . .5 Length variables (see Table 5 for form). . .6 Document layout block clipping insert. . .21 Content portion number of lines
9、 insert 22 Foreword (This foreword is not a part of American Na- tional Standard for Information and Image Management ANSUAIIM MS53-1993 - Standard Recommended Practice - File Format for Storage and Exchange of Im- ages - Bi-Level Image File Format: Part i.) This standard specifies a file format for
10、 the exchange of bi-level, electronic images. Electronic image manage- ment (EIM) systems often use different, and sometimes proprietary, formats for internal storage and processing of images. ANSI/AIIM MS53-1993 provides a standard open interchange format for applications requiring im- age intercha
11、nge, e.g., subsystem integration, image file conversion, remote data input, and image sharing among dissimilar systems. This standard describes a format for the interchange and storage of a bi-level image contained on a single page. This file format is called ALIM Level 1.1 with the recom- mended sh
12、ort identifier being All. The standard has been created because the interchange of images among systems often is difficult. Implemen- tations generally use CCITT facsimile image coding recommendations (standards), originally intended for Group 3 (Recommendations Rec. T.4) and Group 4 (Rec. T.6) facs
13、imile apparatus. When these CCITT recommendations are implemented in facsimile termi- nals, the facsimile “handshake” defines the required parameters that result in successful image transmission. When implemented in equipment other than standardized facsimile terminals without the facsimile “handsha
14、ke,” some parameters are undefined which result in failure of the interchange. ANSUAIIM MS53-1993 provides both the file format and implementation rules for image interchange of CCITT Rec. T.4 and CCITT Rec. T.6 compressed im- ages. It addresses one bit per pel, bi-level imagery, that is either comp
15、ressed or not compressed. The CCITT recommendations for facsimile encoding are sometimes erroneously referred to as Group 3 and Group 4. Group 3 and Group 4 refer to facsimile terminal standards whereas T.4 and T.6 refer to encoding standards. Files written in conformance with any of the pre-defined
16、 file formats defined in this standard, can be imported into an ODA implementation. A program writing an All file simply writes out the data elements in the order and manner specified in section 6.8 (Use of annex A tables). A file formatted according to All consists of six pre- defined subsets of th
17、e ODA file format. Each of the six file formats can be implemented without either techni- cal knowledge or understanding of the ODA format. Ad- ditionally, an ODA implementation is not required to apply this standard. This standard contains seven annexes. Annex A (File for- mat components) is normat
18、ive and is part of this stan- dard. Annexes B (ASN.1 example code), C (Tutorial on ASN.l), D (Uncompressed escape and fill bits), E (Ex- amples of possible output), F (Adding an object wrap- per around All), and G (Suggested reading) are informative and are not to be considered part of this standard
19、. i AIIM MS53 93 m Suggestions for changes or improvements to this standard are welcome and should be sent to the Chair, AHM Standards Board, Association for Information and Image Management, 1100 Wayne Avenue, Suite 1100, Silver Spring, Maryland 20910. The AIIM Standards Board had the following mem
20、bers at the time it approved this standard: Marilyn Courtot, Chair Thomas C. Bagg Thomas E. Berney Loretta DAgnolo Bruce Evans Bruce Holroyd Donald Klosterboer E. Brien Lewis Alan S. Linden Charles A. Plesums George Thoma Charles F. Touchton Herbert J. White, II Association for Information and Image
21、 Management National Institute of Standards and Technology Consultant American Express Company 3M Company Eastman Kodak Company Anacomp, Inc. Wang Laboratories United Services Automobile Association National Library of Medicine IBM Corporation Genealogical Society ;of I-NET, Ic. Utah The AIIM Electr
22、onic Imaging Input Committee, C13, ap- proved this standard. The committee had the following members at the time this standard was approved: Name of Representative Organization Represented Linda Wallace, Chair Larry Albertson Tom Atwood Thomas C. Bagg Alan Bain Gerald Bensi Chuck Biss Bob Blackwelde
23、r Sylvie Bokshorn Robert W. Bristol Bill Cox Wayne Doran Jack Eisen Eric Erickson Jon M. Fech Tom Fine Richard Gershbock Scot Gilheson FileNet Corporation Applied Image, Inc. IMNET Corporation National Institute of Smithsonian Insfitution Bell a document profile, an object descrip- tion, a presentat
24、ion style, a layout style, or a content por- tion description. 3.12 Content portion: The result of partitioning the content of a document according to its logical and/or lay- out structure. 3.13 Content portion description: A constituent of a document, representing a content portion that consists of
25、 content information and attributes to specify the properties of its content information. 3.14 Dimensions: Magnitude in length, width, depth, or time. 2 3.15 Document: (1) Medium and the data recorded on it for human use, for example, a report sheet, a book. (2) By extension, any record that can be
26、read by man or machine. 3.16 Document Application Profile U): The specification of a combination of features defined in CCITT Recommendation T.410 Series (1988 I IS0 8613-1992, Information Technology-Open Document Ar- chitecture (ODA) and Interchange Format, intended to form a subset to fulfill the
27、requirements of an application. 3.17 Document profde: A set of attributes which speci- fies the characteristics of the document as a whole. 3.18 Document layout root: The composite object of the specific layout structure at the highest level of the hierarchy. 3.19 Electronic image: Digital represent
28、ation of a document. 3.20 File structure: The sequence of items inside an interchanged raster file. A document structured in ac- cordance with CCITT Recommendations T.410 Series I IS0 8613 is represented by a data stream consisting of one or more data structures. 3.21 Formatted document architecture
29、: A form of representation of a document that allows the presenta- tion of the document as intended by the originator and that does not support editing and (re)formatting. 3.22 Formatted processable content architecture: A form of raster graphics content architecture which is in- tended to be laid o
30、ut, reformatted and imaged by the recipient in accordance with the originators intent. 3.23 Frame: A type of composite layout component that corresponds to a rectangular area within a page or another frame. 3.24 Interchange: The process of transferring a docu- ment from an originating system to a re
31、ceiving system. 3.25 Layout characteristics: The attributes which guide the layout structure of a layout object. 3.26 Layout object: An element of the specific layout structure of a document, for example, page, block. 3.27 Layout structure: The result of dividing and sub- dividing the content of a d
32、ocument into increasingly smaller parts, on the basis of the presentation, for ex- ample, into pages and blocks. All layout objects and as- sociated content portions forming the layout hierarchy of a document. 3.28 Least significant bits (LSB): When a group of bits is interpreted as a binary value,
33、the least significant bit is the one corresponding to the lowest power of two. 3.29 Line progression: The direction of progression of successive lines of pels within a basic layout object. AIIM MS53 93 = 3.30 Line spacing: The distance between two adjacent lines of pels within a basic layout object.
34、 3.31 Most significant bits (MSB): When a group of bits is interpreted as a binary value, the most significant bit is the one corresponding to the highest power of two. 3.32 Non-basic value: A qualifier for attribute values, control function parameter values and other capabilities that are only allo
35、wed in document interchange in the con- text of a given document application profile if their use is declared in the document profile. 3.33 Open Document Architecture (ODA): An ar- chitecture for compound document representation. See CCITT Rec. T.410 Series I IS0 8613. 3.34 Page: A layout component
36、that corresponds to a rectangular area used for presenting the content of the document. 3.35 Pel: See picture element, 3.39. 3.36 Pel array: A two-dimensional array of pels used to represent a pictorial image. 3.37 Pel path: The direction of progression of succes- sive pels along a line within the b
37、asic layout object. 3.38 Pel spacing: The distance between any two suc- cessive pels along a line within a basic layout object. 3.39 Picture element (pel): Smallest element of a dis- play surface or printed page that can be independently assigned a color or intensity. 3.40 Position: This attribute s
38、pecifies the position of the object relative to the object at the next higher level in the hierarchical structure (i.e., either the immedately superior page of frame or block). 3.41 Positioning area: The rectangular area within a basic layout object within which the position points and the escapemen
39、t points of all character images are located. 3.42 Position point: The point relative to which the character image is placed (Le., the character is imaged with the position point at the active position). 3.43 Presentation attributes: Attributes which guide the format and appearance of an objects con
40、tent. 3.44 Presentation style: A constituent of the document, referred to from a basic logical or layout component, which guides the format and appearance of the document content. 3.45 Raster graphics: Method of representing a two- dimensional image by dividing it into a rectangular two- dimensional
41、 array of picture elements. See also electronic image, 3.19, and pel, 3.35. 3.46 Raster graphics attributes: A set of attributes that includes pel path, line progression, clipping, and pel spacing. 1012348 0500160 206 3.47 Spacing ratio: The ratio of line spacing to pel spacing. 3.48 Type of coding:
42、 This attribute specifies the cod- ing used to represent the content, and designates any set of additional coding attributes applicable to the content portion (Le., number-of-pels-per-line, number-of-lines, compression). 4 Format of variables This section contains three tables that describe the vari
43、- ables used in the tables in annex A. In table 1, Restrict- ed variables, these variables have a limited choice of values. In table 2, Integer variables, these variables con- tain integer parameters describing the image, (e.g., the number of pels per line). In table 3, Length variables, each of the
44、se variables is used to specify the length of its following ODA-based structure. These structures may use terminology from ODA which is not essential to an understanding of the All file format. For tables 1,2 and 3 turn to pages 4, 5 and 6. 5 Introduction Image compression standards are applied in i
45、nformation systems to reduce the amount of data storage that is re- quired for digital document images. This standard de- fines an implementation of image compression standards and technologies that are described in CCITT Recom- mendations T.4 and T.6 for electronic document/image scanning, storage,
46、 and retrieval systems that are used in non-facsimile environments. The goal of this standard is to provide a format for the interchange of encoded compressed or uncompressed im- ages. Implementing this standard will allow applications to produce a file format that will be intelligible by other syst
47、ems implementing the same standard. This standard is based on CCITT Recommendations in the T.410 series I IS0 8613, Open Document Architec- ture (ODA) and Interchange Format. However, knowledge of ODA (or its ASN.l syntax) is not required by an individual implementing this standard. Addition- ally,
48、an ODA environment is not required to apply this standard as a simple pattern match algorithm can be used to parse the All header. Since CCITT Rec. T.410 series I ISO/IEC 8613 (ODA) is a very comprehensive stan- dard, agreements have been reached among irnplemen- tors and service providers on common
49、 subsets of ODA. These agreements are called Document Application Pro- files (DAPs), and several have been standardized inter- nationally. ODA is an architecture which can be used to describe a large variety of compound documents. It facilitates open interchange of documents in processable (revisable) form, formatted (page image) form, or both. The docu- ments content may consist of character coded text, raster 3 AIIM MS53 93 1012348 05001bL 142 W Table 1 Restricted variables Description Occurs in Values (hexadecimal) s1 c2 c3 c4 Choice of: 58 03 07 O0 58 03 07 O1
