1、 Reference number ISO/IEC 15415:2011(E) ISO/IEC 2011INTERNATIONAL STANDARD ISO/IEC 15415 Second edition 2011-12-15 Information technology Automatic identification and data capture techniques Bar code symbol print quality test specification Two- dimensional symbols Technologies de linformation Techni
2、ques automatiques didentification et de capture des donnes Spcification de test de qualit dimpression des symboles de code barres Symboles bidimensionnels ISO/IEC 15415:2011(E) COPYRIGHT PROTECTED DOCUMENT ISO/IEC 2011 All rights reserved. Unless otherwise specified, no part of this publication may
3、be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. +
4、 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO/IEC 2011 All rights reservedISO/IEC 15415:2011(E) ISO/IEC 2011 All rights reserved iiiContents Page Foreword . v Introduction vi 1 Scope 1 2 Normative references 1 3 Terms and definitions .
5、 2 4 Symbols and abbreviated terms 3 5 Quality grading 3 5.1 General . 3 5.2 Expression of quality grades . 4 5.3 Overall Symbol Grade . 4 5.4 Reporting of symbol grade . 5 6 Measurement methodology for two-dimensional multi-row bar code symbols . 5 6.1 General . 5 6.2 Symbologies with cross-row sca
6、nning ability . 6 6.2.1 Basis of grading 6 6.2.2 Grade based on analysis of scan reflectance profile 6 6.2.3 Grade based on Codeword Yield . 7 6.2.4 Grade based on unused error correction . 8 6.2.5 Grade based on codeword print quality 9 6.2.6 Overall symbol grade 10 6.3 Symbologies requiring row-by
7、-row scanning 11 7 Measurement methodology for two-dimensional matrix symbols . 11 7.1 Overview of methodology 11 7.2 Obtaining the test images. 12 7.2.1 Measurement conditions 12 7.2.2 Raw image 12 7.2.3 Reference grey-scale image . 12 7.2.4 Binarised image . 13 7.3 Reference reflectivity measureme
8、nts 13 7.3.1 General requirements . 13 7.3.2 Light source . 13 7.3.3 Effective resolution and measuring aperture . 13 7.3.4 Optical geometry . 14 7.3.5 Inspection area 16 7.4 Number of scans . 16 7.5 Basis of scan grading . 16 7.6 Grading procedure 16 7.7 Additional reflectance check over extended a
9、rea 17 7.8 Image assessment parameters and grading 17 7.8.1 Use of reference decode algorithm . 17 7.8.2 Decode 17 7.8.3 Symbol Contrast 18 7.8.4 Modulation and related measurements . 18 7.8.5 Fixed Pattern Damage . 21 7.8.6 Axial Nonuniformity 21 7.8.7 Grid Nonuniformity 22 7.8.8 Unused error corre
10、ction . 23 7.8.9 Additional grading parameters 23 ISO/IEC 15415:2011(E) iv ISO/IEC 2011 All rights reserved7.9 Scan grading 23 7.10 Overall Symbol Grade .24 7.11 Print growth 24 8 Measurement methodologies for composite symbologies .24 9 Substrate characteristics 25 Annex A (normative) Symbology-spe
11、cific parameters and values for symbol grading 26 Annex B (informative) Symbol grading flowchart for two-dimensional matrix symbols .30 Annex C (informative) Interpreting the scan and symbol grades 31 Annex D (informative) Guidance on selection of grading parameters in application specifications .33
12、 Annex E (informative) Substrate characteristics .39 Annex F (informative) Parameter grade overlay applied to two-dimensional symbologies 41 Bibliography 42 ISO/IEC 15415:2011(E) ISO/IEC 2011 All rights reserved vForeword ISO (the International Organization for Standardization) and IEC (the Internat
13、ional Electrotechnical Commission) form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC participate in the development of International Standards through technical committees established by the respective organization to deal with particular field
14、s of technical activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information technology, ISO and IEC have established a jo
15、int technical committee, ISO/IEC JTC 1. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of the joint technical committee is to prepare International Standards. Draft International Standards adopted by the joint technical committ
16、ee are circulated to national bodies for voting. Publication as an International Standard requires approval by at least 75 % of the national bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO and IEC shall
17、not be held responsible for identifying any or all such patent rights. ISO/IEC 15415 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 31, Automatic identification and data capture techniques. This second edition cancels and replaces the first edition (
18、ISO/IEC 15415:2004), which has been technically revised. It also incorporates the Technical Corrigendum ISO/IEC 15415:2004/Cor.1:2008. ISO/IEC 15415:2011(E) vi ISO/IEC 2011 All rights reservedIntroduction The technology of bar coding is based on the recognition of patterns encoded, in bars and space
19、s or in a matrix of modules of defined dimensions, according to rules defining the translation of characters into such patterns, known as the symbology specification. Symbology specifications may be categorised into those for linear symbols, on the one hand, and two-dimensional symbols on the other;
20、 the latter may in turn be sub-divided into “multi-row bar code symbols”, sometimes referred to as “stacked bar code symbols”, and “two-dimensional matrix symbols”. In addition, there is a hybrid group of symbologies known as “composite symbologies”; these symbols consist of two components carrying
21、a single message or related data, one of which is usually a linear symbol and the other a two-dimensional symbol positioned in a defined relationship with the linear symbol. Multi-row bar code symbols are constructed graphically as a series of rows of symbol characters, representing data and overhea
22、d components, placed in a defined vertical arrangement to form a (normally) rectangular symbol, which contains a single data message. Each symbol character has the characteristics of a linear bar code symbol character and each row has those of a linear bar code symbol; each row, therefore, may be re
23、ad by linear symbol scanning techniques, but the data from all the rows in the symbol must be read before the message can be transferred to the application software. Two-dimensional matrix symbols are normally square or rectangular arrangements of dark and light modules, the centres of which are pla
24、ced at the intersections of a grid of two (sometimes more) axes; the coordinates of each module need to be known in order to determine its significance, and the symbol must therefore be analysed two-dimensionally before it can be decoded. Dot codes are a subset of matrix codes in which the individua
25、l modules do not directly touch their neighbours but are separated from them by a clear space. Unless the context requires otherwise, the term “symbol” in this International Standard may refer to either type of symbology. The bar code symbol must be produced in such a way as to be reliably decoded a
26、t the point of use, if it is to fulfil its basic objective as a machine-readable data carrier. Manufacturers of bar code equipment and the producers and users of bar code symbols therefore require publicly available standard test specifications for the objective assessment of the quality of bar code
27、 symbols (a process known as verification), to which they can refer when developing equipment and application standards or determining the quality of the symbols. Such test specifications form the basis for the development of measuring equipment for process control and quality assurance purposes dur
28、ing symbol production as well as afterwards. The performance of measuring equipment for the verification of symbols (verifiers) is the subject of a separate International Standard (ISO/IEC 15426, Parts 1 and 2). This International Standard is intended to achieve comparable results to the linear bar
29、code symbol quality standard ISO/IEC 15416, the general principles of which it has followed. It should be read in conjunction with the symbology specification applicable to the bar code symbol being tested, which provides symbology- specific detail necessary for its application. Two-dimensional mult
30、i-row bar code symbols are verified according to the ISO/IEC 15416 methodology, with the modifications described in Clause 6; different parameters and methodologies are applicable to two-dimensional matrix symbols. There are currently many methods of assessing bar code quality at different stages of
31、 symbol production. The methodologies described in this International Standard are not intended as a replacement for any current process control methods. They provide symbol producers and their trading partners with universally standardized means for communicating about the quality of multi-row bar
32、code and two-dimensional matrix symbols after they have been printed. The procedures described in this International Standard must necessarily be augmented by the reference decode algorithm and other measurement details within the ISO/IEC 15415:2011(E) ISO/IEC 2011 All rights reserved viiapplicable
33、symbology specification, and they may also be altered or overridden as appropriate by governing symbology or application specifications. Alternative methods of quality assessment may be agreed between parties or as part of an application specification. For direct part mark applications, a modified v
34、ersion of the methodology defined in this International Standard has been defined in ISO/IEC TR 29158. INTERNATIONAL STANDARD ISO/IEC 15415:2011(E) ISO/IEC 2011 All rights reserved 1Information technology Automatic identification and data capture techniques Bar code symbol print quality test specifi
35、cation Two-dimensional symbols 1 Scope This International Standard specifies two methodologies for the measurement of specific attributes of two-dimensional bar code symbols, one of these being applicable to multi-row bar code symbologies and the other to two- dimensional matrix symbologies; defines
36、 methods for evaluating and grading these measurements and deriving an overall assessment of symbol quality; gives information on possible causes of deviation from optimum grades to assist users in taking appropriate corrective action. This International Standard applies to those two-dimensional sym
37、bologies for which a reference decode algorithm has been defined, but its methodologies can be applied partially or wholly to other similar symbologies. While this International Standard can be applied to direct part marks, it is possible that better correlation between measurement results and scann
38、ing performance will be obtained with ISO/IEC TR 29158 in combination with this International Standard. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the
39、latest edition of the referenced document (including any amendments) applies. ISO/IEC 19762-1, Information technology Automatic identification and data capture (AIDC) techniques Harmonized vocabulary Part 1: General terms relating to AIDC ISO/IEC 19762-2, Information technology Automatic identificat
40、ion and data capture (AIDC) techniques Harmonized vocabulary Part 2: Optically readable media (ORM) ISO 7724-2:1984, Paints and varnishes Colorimetry Part 2: Colour measurement ISO/IEC 15416, Information technology Automatic identification and data capture techniques Bar code print quality test spec
41、ification Linear symbols NOTE The Bibliography lists official and industry standards containing specifications of symbologies to which (inter alia) this International Standard is applicable. ISO/IEC 15415:2011(E) 2 ISO/IEC 2011 All rights reserved3 Terms and definitions For the purposes of this docu
42、ment, the terms and definitions given in ISO/IEC 19762-1, ISO/IEC 19762-2, ISO/IEC 15416 and the following apply. 3.1 binarised image binary (black/white) image created by applying the Global Threshold to the pixel values in the reference grey- scale image 3.2 effective resolution resolution obtaine
43、d on the surface of the symbol under test, normally expressed in pixels per millimetre or pixels per inch, and calculated as the resolution of the image capture element multiplied by the magnification of the optical elements of the measuring device 3.3 error correction capacity number of codewords i
44、n a symbol (or error control block) assigned for erasure and error correction, minus the number of codewords reserved for error detection 3.4 inspection area rectangular area which contains the entire symbol to be tested inclusive of its quiet zones 3.5 grade threshold boundary value separating two
45、grade levels, the value itself being taken as the lower limit of the upper grade 3.6 module error module of which the apparent dark or light state in the binarised image is inverted from its intended state 3.7 pixel individual light-sensitive element in an array e.g. CCD (charge coupled device) or C
46、MOS (complementary metal oxide semiconductor) device 3.8 raw image plot of the reflectance values in x and y coordinates across a two-dimensional image, representing the discrete reflectance values from each pixel of the light-sensitive array 3.9 reference grey-scale image plot of the reflectance va
47、lues in x and y coordinates across a two-dimensional image, derived from the discrete reflectance values of each pixel of the light-sensitive array by convolving the raw image with a synthesised circular aperture 3.10 reflectance margin measurement of modulation using error correction and known modu
48、le colours 3.11 sample area area of an image contained within a circle 0,8X in diameter, X being the average module width determined by the application of the reference decode algorithm for the symbology in question or, where the application permits a range of X dimensions, the minimum module width
49、permitted by the application specification ISO/IEC 15415:2011(E) ISO/IEC 2011 All rights reserved 33.12 scan grade result of the assessment of a single scan of a matrix symbol, derived by taking the lowest grade achieved for any measured parameter of the reference grey-scale and binarised images 4 Symbols and abbreviated terms AN = Axial Nonuniformity E cap= error correction capacity of the symbol e = number of erasures FPD = Fixed Pattern Damage GN = Grid Nonuniformity GT = Global Threshold MARGI
