ANSI INCITS ISO 1073-2-1976 Alphanumeric character sets for optical recognition - Part II Character set OCR-B - Shapes and dimensions of the printed image.pdf

1、INTERNATIONAL STANDARD 1073/l INTERNATIONAL ORGANIZATION FOR STANDARDIZATION -MEW?.YHAPOHAR OPrAHM3AUMR “0 CTAHaAPTW3AUAA.ORGANISATION INTEANATIONALE DE NORMALISATION Alphanumeric character sets for optical recognition - Part II : Character set OCR-B - Shapes and dimensions of the printed image Jeux

2、 alphanumt+iques de carackes pour la reconnaissance optique - Partie II : Jeu de caracttkes ROC-B - Formes et totes de Iimage imprimbe First edition - 1976 -12 -01 Corrected and reprinted - 1979 -06 -15 co 6 7 = UDC 681.3.048 Ref. No. IS0 1073111-1976 (E) ;i s Descriptors : data processing, optical

3、recognition, alphanumeric character sets, OCR-B character sets, specifications, dimensions. E Price based on 54 pages Adopted by INCITS (InterNational Committee for Information Technology Standards) as an American National Standard.Date of ANSI Approval: 1/11/99Published by American National Standar

4、ds Institute,25 West 43rd Street, New York, New York 10036Copyright 2002 by Information Technology Industry Council (ITI).All rights reserved.These materials are subject to copyright claims of International Standardization Organization (ISO), InternationalElectrotechnical Commission (IEC), American

5、National Standards Institute (ANSI), and Information Technology Industry Council(ITI). Not for resale. No part of this publication may be reproduced in any form, including an electronic retrieval system, withoutthe prior written permission of ITI. All requests pertaining to this standard should be s

6、ubmitted to ITI, 1250 Eye Street NW,Washington, DC 20005.Printed in the United States of AmericaFOREWORD IS0 (the International Organization for Standardization) is a worldwide federation of national standards institutes (IS0 Member Bodies). The work of developing International Standards is carried

7、out through IS0 Technical Committees. Every Member Body interested in a subject for which a Technical Committee has been set up has the right to be represented on that Committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. Draft In

8、ternational Standards adopted by the Technical Committees are circulated to the Member Bodies for approval before their acceptance as International Standards by the IS0 Council. International Standard IS0 1073/ll was drawn up by Technical Committee ISO/TC 97, Computers and information processing, an

9、d was circulated to the Member Bodies in May 1975. It has been approved by the Member Bodies of the following countries : Australia Hungary Belgium Italy Brazil Japan Czechoslovakia Netherlands Denmark New Zealand France Romania Germany South Africa, Rep. of Sweden Switzerland Turkey United Kingdom

10、U.S.A. U.S.S.R. Yugoslavia No Member Body expressed disapproval of the document. This International Standard, together with IS0 1073/l, cancels and replaces IS0 Recommendation R 1073-1969. 0 International Organization for Standardization, 1976 l Printed in Switzerland INTERNATIONAL STANDARD IS0 1073

11、/ll-1976 (E) Alphanumeric character sets for optical recognition - Part II : Character set OCR-B - Shapes and dimensions of the printed image 1 GENERAL 1.1 Scope This International Standard for character shapes and sizes is intended to facilitate and foster the use of Optical Character Recognition (

12、OCR) in data processing, by defining character shapes suitable for both human and machine reading. It establishes a common basis for printing equipment and optical scanning equipment for OCR interchange appli- cations. Additional International Standards will cover the print quality and the relevant

13、characteristics of the formats needed to satisfy interchange requirements. 1.2 Field of application This International Standard specifies the printed image shapes and sizes of alphanumeric characters, graphics and symbols designed for use in Optical Character Recognition. They are also suitable for

14、general purposes. In order to satisfy present requirements and encourage the wide extension of OCR applications, two sets of characters are specified. These are named OCR-A and OCR-B. Character set OCR-A includes the numeric sub-set which was recommended in draft IS0 Recommendation No. 890 (now part

15、 of this International Standard). The shapes of the characters have been designed to be suitable for use in many applications of OCR. Dimensions of OCR-A are given in three sizes. (See part I.) The shapes of the OCR-B characters have been designed for use in OCR systems without undue sacrifice of th

16、eir suit- ability for general purposes in a wide range of applications. Dimensions of OCR-B are given in three sizes. 1.3 Definitions For the purpose of this International Standard the follow- ing definitions apply : 1.3.1. OCR-A : A repertoire of 69 characters of which 56 are graphics included in t

17、he IS0 7-bit coded character set (IS0 646-1973). It comprises digits, capital letters, capital national letters and other graphics. (See part I.) 1.3.2 OCR-B : A repertoire of 121 characters comprising digits, capital and small letters, all the graphics specified in the IS0 7-bit coded character set

18、 (IS0 646-19731, national letters, diacritical signs and further graphics. NOTES 1 For applications which involve circulation of documents across boundaries between areas in which different national characters are in use, agreement between the sender and the recipient of the documents is required. 2

19、 The metric and inch dimensions in this International Standard are rounded and therefore consistent but not exactly equal. Either system may be used but the two should not be intermixed. 3 It is recognized that some type-making and printing processes will not be able to produce sharp corners. Corner

20、s not specified as having a specific radius should be as sharp as practicable. However, it is not necessary for OCR purposes that the radii of the corners of the nominal printed image be less than 0.08 mm (0.003 5 in). 2 STYLES The OCR-B font (see clause 13) comprises 121 characters, but, in general

21、, only a subset will be used for a specific application. The character shapes and dimensions are specified by refer- ence drawings on a reference grid. The nominal strokewidth is constant for each character of the standard set entitled “constantstrokewidth font”; the centreline of each character is

22、indicated on the reference grid. A second style of characters entitled “letterpress font” may be used with printing equipment which can reproduce fine details with sufficient accuracy. For many classes of printers, however, the strokewidth is less controllable and therefore for these printers the co

23、nstant-strokewidth font shall be used. For aesthetic reasons, the strokewidth of the letterpress font characters is varied deliberately and the stroke endings are specially designed. But the centrelines are the same for both fonts and these centrelines, as defined for the constant- strokewidth font,

24、 are the definitive part of this standard. 3 OCR-B SIZES 3.1 Three sizes are specified for OCR-B characters in order to provide for use with a wide range of printing equipment processing differing print quality characteristics. Devices such as typewriters, cash registers, numbering machines, high-sp

25、eed printers, and credit card imprinters, besides printing processes such as letterpress and offset lithography, are all suitable. 1 IS0 1073/11-1976 (E) 3.2 The letterpress font is specified in size I (the smallest) 3.7 The widest character in each size (except for the only. It provides the option

26、of a variable pitch between alternative small letter m) is digit ZERO. Its centreline characters as is usual with letterpress. widths are : 3.3 The constant-strokewidth font is specified in three sizes, I, III and IV. Mechanisms using the constant- strokewidth font will usually maintain a fixed pitc

27、h. 3.4 Size I I which was in ISO/R 1073-1969 has been deleted. (See annex B.) 3.5 The centrelines for the three sizes are simply related by appropriate horizontal and vertical scale factors. The factors for size III and size IV referred to size I are : for size III Vertical : 1,333 Horizontal : 1,08

28、6 for size IV Vertical : 1,500 Horizontal : 1,500 This scale relationship does not apply to the outline shapes, since nominal strokewidth is not strictly proportional to centreline dimensions. The strokewidths for each size are shown in the reference drawings. 3.6 The character with the greatest hei

29、ght in each size is digit EIGHT. It is the character which extends farthest above the base line for capital letters. The longest charac- ter is small letter j, because of its descender. The centreline heights of the character EIGHT are : for size I : 2,40 mm (0.094 in) for size III : 3,20 mm (0.126

30、in) for size IV : 3,60 mm (0.142 in) for size I : for size III : for size IV : I,40 mm (0.055 in) 1.52 mm (0.060 in) 2.10 mm (0.083 in) 3.8 Constant-pitch printing In constant-pitch printing for OCR applications, the follow- ing minimum nominal pitches are appropriate : size I : 2.54 mm (0.100 in) m

31、in. size III : 2.54 mm (0.100 in) min. size IV : 3.63 mm (0.143 in) min. 4 TYPICAL DIMENSIONS OF THE NOMINAL PRINTED IMAGE 4.1 Constant-strokewidth font Typical dimensions for the nominal printed image of the constant-strokewidth font in size I are given below. These dimensions are the heights above

32、 and below the horizontal base line of digits, capital and small letters, ascenders and descenders (see figure 1). These dimensions are for general information only. The values for individual characters are obtainable from the reference drawings. 4.2 Letterpress font The shapes of the letterpress ch

33、aracters are similar except that the stroke ends are not rounded. H) FIGURE 1 - Heights above and below base line TABLE 1 - Typical dimensions A, B, C and D millimetres inches Size A B C D A B c D I 2.66 2.46 1.83 0,60 0.105 0.097 0.072 0.024 2 IS0 1073/ll-1976 (E) 5 OCR-B CHARACTER SET The full cha

34、racter set comprises 121 characters. The following sub-sets can be distinguished. 5.1 Sub-set 1 : Numeric sub-set This sub-set comprises 22 characters : 0123456789 CENSTXZ i SPACE NOTES 1 The character ZERO is the only digit which had to be modified in this revision of ISOlR 1073-1969. The use of th

35、e original design is toler- ated in numeric applications implemented before 1976. OCR reading of both old and revised design is subject to special agreement between OCR equipment supplier and user. For any application implemented after 1976, only the new design is standard. 2 The characters C E N S

36、T X Z should preferably not be used in document reading applications. 5.2 Sub-set 2 : Initial alphanumeric sub-set This sub-set comprises 47 characters : 0123456789 ABCDEFGHIJKLM NOPQRSTUVWXYZ *-=I., 1 SPACE 3 IS0 1073/ll-1976 (E) 5.3 Sub-set 3 : Extended alphanumeric sub-set This sub-set comprises

37、98 characters, in particular those of the IS0 7-bit coded character set (IS0 646-1973) : “#f#$%? ABCDEFGHIJKLMNO PQRSTUVWXYzC7”_ abcdefghijklmno pqrstuvwxyz(Y I 1 SPACE 5.4 Sub-set 4 : Options sub-set This sub-set comprises 8 capital national letters, 5 small national letters, 4 diacritical signs an

38、d 4 further characters : m 4 IS0 1073/11-1976 (E) 5.5 Sub-set 5 : Erase characters This sub-set comprises 2 characters : CHARACTER ERASE GROUP ERASE - - The dimensions of these two characters are as shown below : I c W x I L min. - I CHARACTER ERASE CHARACTER ERASE : min. H max. H min. W max. W D GR

39、OUP ERASE : minimum length minimum width a b BASE LINE UPPER LIMIT OF UPPER EDGE LOWER LIMIT OF LOWER EDGE BASE LINE GROUP ERASE FIGURE 2 - Erase characters TABLE 2 - Dimensions of erase characters millimetres T inches Size I Size III Size IV Size I Size III Size IV 2.4 33 0.094 0.149 2.9 4.6 0.115

40、0.181 I,4 2.0 0.055 0.079 1.9 2.8 0.075 0.110 0,13 0.20 0.005 0.008 7.6 7.6 10,9 0.300 0.300 0.430 0.2 0.2 0.2 0.008 0.008 0.008 0.4 0.5 0.6 0.016 0.020 0.024 2.0 2.7 3,O 0.077 0.106 0.118 1 IS0 1073/ll-1976 (E) 6 INDEX TABLE 6.1 All characters are available in size I as constant- strokewidth font a

41、nd as letterpress font. Only the characters of the numeric sub-set (sub-set 1) and the character GROUP ERASE are available in size Ill as constant-strokewidth font. All characters are available in size IV as constant-strokewidth font, with the exception of VERTICAL LINE. 6.2 In the following index t

42、able each character is given with the indication of the reference drawing or drawings and the sub-set or sub-sets in which it is comprised. The drawings are identified as follows : L : for letterpress font, size I C : for the constant-strokewidth font, size I I I I : for the constant-strokewidth fon

43、t, size I I I. 6.3 As stated in 11.6, the character shapes for size IV are derived from those of size I for the constant-strokewidth font (designated by C). 6.4 Application advice is given in the column “Remarks”, where it is indicated, inter alia, which characters are in- cluded for general-purpose

44、 use only and should not be used for OCR purposes. It is recommended that prospective users of this standard consult manufacturers before deciding on a particular character set. 6 IS0 1073/ll-1976 (E) Ref. No. 1 2 5 6 6 9 IO 11 Shape 1 2 3 4 5 8 9 0 A Drawing(s) No. 1 L, c, III 2 L, c III 3 L, c, II

45、I 4 L, c, III 5 L, c, III 6 L, c, III 7 L, c, III 8 L, c, III 9 L, c, III IO L, c, III 11 L, c INDEX TABLE Name Sets Remarks DIGIT 1 2 ONE 3 DIGIT 1 2 TWO 3 DIGIT 1 2 THREE 3 DIGIT 1 2 FOUR 3 DIGIT 1 2 FIVE 3 DIGIT 1 2 SIX 3 DIGIT 1 SEVEN 2 3 DIGIT 1 2 EIGHT 3 DIGIT 1 2 NINE 3 DIGIT 1 2 ZERO 3 The c

46、haracter ZERO is the only digit which had to bt modified in this revision of ISO/R 1073-1969. The use o the original design is tolerated in numeric application! implemented before 1976. OCR reading of both old ant revised design is subject to special agreement betweer OCR equipment supplier and user

47、. For any applicatior implemented after 1976. only the new design is standard CAPITAL LETTER 2 A 3 IS0 1073/ll-1976 (E) INDEX TABLE (continued) Ref. No. 12 Shape Drawingls) Remarks No. Name Sets B 12 CAPITAL LETTER 2 L c B 3 13 CAPITAL LETTER 1 13 C 2 L, c, III C 3 D 14 CAPITAL LETTER 2 14 L. c D 3

48、15 CAPITAL LETTER 1 15 E 2 L, c, III E 3 16 F 16 CAPITAL LETTER 2 L c F 3 17 G 17 CAPITAL LETTER 2 L c G 3 18 H 18 CAPITAL LETTER 2 L c H 3 19 19 I CAPITAL LETTER 2 L c I 3 J 20 20 CAPITAL LETTER 2 L c J 3 21 K 21 CAPITAL LETTER 2 L c K 3 22 22 L CAPITAL LETTER 2 L. c L 3 8 IS0 1073/11-1976 (E) INDE

49、X TABLE (continued) Ref. No. Shape Drawing(s) No. Name Sets Remarks 23 M 23 CAPITAL LETTER 2 L c M 3 24 N 24 CAPITAL LETTER 1 2 L, c, III N 3 25 0 25 CAPITAL LETTER 2 L c 0 3 26 P 26 CAPITAL LETTER 2 L, c P 3 27 Q 27 CAPITAL LETTER 2 L c Q 3 28 R 28 CAPITAL LETTER 2 L c R 3 29 1 29 S CAPITAL LETTER 2 L, c, III S 3 30 T 30 CAPITAL LETTER 1 T 2 L, c, III 3 U 31 31 CAPITAL LETTER 2 L. c U 3 32 V 32 CAPITAL LETTER 2 L c v 3 33 W 33 CAPITAL LETTER 2 L c W 3 9 IS0 1073/11-1976 (E) INDEX TABLE (continued) Ref. No. Shape Drawing(s) No. Name Sets Remarks 34 1 34 X CAPITAL LETTER 2 L, c, III X