ANSI INCITS 17-1981 Character Set for Optical Character Recognition (OCR-A).pdf
《ANSI INCITS 17-1981 Character Set for Optical Character Recognition (OCR-A).pdf》由会员分享,可在线阅读,更多相关《ANSI INCITS 17-1981 Character Set for Optical Character Recognition (OCR-A).pdf(53页珍藏版)》请在麦多课文档分享上搜索。
1、Chap Chap kNSI INCITS 17-1981 (R2000) (formerly ANSI X3.17- 198 1 (R2000) ADOPTED FOR USE BY THE FEDERAL GOVERNMENT WA- b PUB 32-1 SEE NOTICE ON INSIDE aacter Set for Optical aacter Recognition (OCR-A) De SM Where IT all begins This standard has been adopted for Federal Government use. Details conce
2、rning its use within the Federal Government are contained in FIPS PUB 32-1, Character Sets for Optical Character Recognition (OCR). For a com- plete list of the publications available in the Federal Information Processing Standards series, write to the Standards Processing Coordinator, Institute for
3、 Computer Sciences and Technology, National Bureau of Standards, Washington, D.C. 20234. ANSI X3.17-1981 Revision of ANSI X3.17-1977 American National Standard Character Set for Optical Character Recognition (OCR-A) Secretariat Computer and Business Equipment Manufacturers Association Approved June
4、16, 1981 American National Standards institute, inc Abstract This standard provides the description, scope, and identification for a set of graphic shapes to be used in the application of optical character recognition (OCR) systems. The style is desig- nated OCR-A and comprises 96 graphic shapes, pl
5、us the Character Space. OCR-A was designed to provide maximum machine efficiency under a wide range of applications. Three sizes of graphic shapes are provided - I, I Il, and IV (I I is reserved for certain international applications). In addition to graphic shapes and related information, the stand
6、ard provides basic requirements related to character positioning and the ASCII code table Key words: optical character recognition, OCR, OCR-A, graphic shapes, character positioning, data entry, machine reading. Approval of an American National Standard requires review by ANSI that the requirements
7、for due process, consensus, and other criteria for approval have been met by the standards developer. Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement mean
8、s much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that a concerted effort be made toward their resolution. The use of American National Standards is completely voluntary; their existence does not in any respect prec
9、lude anyone, whether he has approved the standards or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standards. The American National Standards Institute does not develop standards and will in no circumstances give an interpretation
10、of any American National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. Requests for interpretations should be addressed to the secretariat or sponsor whose name app
11、ears on the title page of this standard. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken periodically to reaffirm, revise, or withdraw this standard. Purchasers of Americ
12、an National Standards may receive current information on all standards by calling or writing the American National Standards Institute. American National Published by American National Standards Institute 11 West 42nd Street, New York, New York 10036 Copyright O1 981 by Information Technology Indust
13、ry Council (ITI) All rights reserved. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior written permission of ITI, 1250 Eye Street NW, Washington, DC 20005. Printed in the United States of America Foreword (This Foreword is not a
14、 part of Amencan National Standard Character Set for Optical Character Recognition (OCR-A), ANSI X3.17-1981.) This standard presents an alphanumeric character set for use in optical character recognition (OCR) systems. The character set contains 96 printing characters plus the Character Space, and i
15、ncludes digits, letters, small letters, and special symbols. Two editing characters, Character Erase and Group Erase, are also included. Alternate shapes are provided for the Period, Comma, Question Mark, Hyphen (Minus Sign), and the Apostrophe to improve performance in some printing devices and to
16、improve recognition. The character set includes an OCR representation for all 96 characters in American National Standard Code for Information Interchange (ASCII), ANSI X3.4-1977. No graphic shapes were developed for the ASCII characters Tilde, Underline, and Grave Accent, since any need for these g
17、raphics could be represented in their respective code positions by the Hook, Fork, and Chair (if required in an information interchange application). The character set repertoire and character shape specifications in this standard are identical to those contained in American National Standard Charac
18、ter Set and Print Quality for Optical Character Recognition (OCR-A), ANSI X3.17-1977. This standard, containing only character shapes and their nominal position, is a refinement of and supersedes ANSI X3.17-1977. Speci- fications for character positioning are contained in American National Standard
19、for Optical Character Recognition (OCR) Character Positioning, ANSI X3.93M-1981. The OCR-A character set for optical character recognition was first developed in the United States in 1961 as a numeric font only. In 1966 an alphanumeric font which contained 57 char- acters, including the existing num
20、eric font, 4 abstract characters, and only capital letters, was issued. The revised standard was entitled American National Standard Character Set for Optical Character Recognition, ANSI X3.17-1966. A revised edition was published in 1974, as American National Standard Character Set and Print Qualit
21、y for Optical Character Recognition (OCR-A), ANSI X3.17-1974. It contained an en- larged repertoire of 86 characters by including the small letter alphabet and 3 new characters, Character Space, Character Erase, and Group Erase. Also, 5 alternate characters to improve printing and readability of the
22、 Period, Comma, Question Mark, Apostrophe, and Hyphen were added. Specifications for spectral bands, paper, character positioning, and print quality were expanded. The OCR-A standard was revised in 1977 to enlarge the character set repertoire to 97 standard characters by the addition of 11 new chara
23、cters. All OCR characters were assigned positions in the ASCII code table. This revised edition was issued as ANSI X3.17-1977. Other standards of interest in this field are published by the International Organization for Standardization (ISO) as International Standard IS0 1073/I-1976, Alphabetic cha
24、racter sets for optical recognition - Part I: Character set OCR-A - Shapes and dimensions of the printed image, and IS0 1073/11-1976, Alphanumeric character sets for optical recognition - Part II: Character set OCR-B - Shapes and dimensions of the printed image. The character shapes speci- fied in I
- 1.请仔细阅读文档,确保文档完整性,对于不预览、不比对内容而直接下载带来的问题本站不予受理。
- 2.下载的文档,不会出现我们的网址水印。
- 3、该文档所得收入(下载+内容+预览)归上传者、原创作者;如果您是本文档原作者,请点此认领!既往收益都归您。
下载文档到电脑,查找使用更方便
10000 积分 0人已下载
下载 | 加入VIP,交流精品资源 |
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- ANSIINCITS171981CHARACTERSETFOROPTICALCHARACTERRECOGNITIONOCRAPDF

链接地址:http://www.mydoc123.com/p-435520.html