1、INTERNATIONAL STANDARD ISOIIEC 109184 First edition 1994-02-15 Information technology - Digital compression and coding of continuous-tone still images: Requirements and guidelines Technologies de /information - Compression numdrique et codage des images fixes de nature photographique: Prescriptions
2、et lignes directrices Reference number ISOAEC 10918-1:1994(E) Processed and adopted by ASC NCITS and approved by ANSI as an American National Standard.Date of ANSI Approval: 1/11/99Published by American National Standards Institute,11 West 42nd Street, New York, New York 10036Copyright 1999 by Infor
3、mation Technology Industry Council (ITI).All rights reserved.These materials are subject to copyright claims of International Standardization Organization (ISO),International Electrotechnical Commission (IEC), American National Standards Institute (ANSI), andInformation Technology Industry Council (
4、ITI). Not for resale. No part of this publication may be reproducedin any form, including an electronic retrieval system, without the prior written permission of ITI. All requestspertaining to this standard should be submitted to ITI, 1250 Eye Street NW, Washington, DC 20005.Printed in the United St
5、ates of AmericaAdopted by INCITS (InterNational Committee for Information Technology Standards) as an American National Standard.Date of ANSI Approval: 1/11/99Published by American National Standards Institute,25 West 43rd Street, New York, New York 10036Copyright 2002 by Information Technology Indu
6、stry Council (ITI).All rights reserved.These materials are subject to copyright claims of International Standardization Organization (ISO), InternationalElectrotechnical Commission (IEC), American National Standards Institute (ANSI), and Information Technology Industry Council(ITI). Not for resale.
7、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 submitted to ITI, 1250 Eye Street NW,Washington, DC 20005.Printed in the United States of AmericaCopyrig
8、ht American National Standards Institute Provided by IHS under license with ANSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-ISO/IEC10918-1:1994(E) Contents Page 1 scope 1 2 Normative references 1 3 Definitions, abbreviations and symbols . 1 4 General . 12 5 Int
9、erchange format requirements . 23 6 Encoder requirements . 23 7 Decoder requirements . 23 Annexes A Mathematical definitions 24 B Compressed data formats 3 1 C Huffman table specification 50 D Arithmetic coding ; 54 E Encoder and decoder control procedures . 77 F Sequential DCT-based mode operation
10、. 87 G Progressive DCT-based mode of operation . 119 H Lossless mode of operation . 132 J Hierarchical mode of operation . 137 K Examples and guidelines . 143 L Patents 179 M Bibliography . 181 63 ISO/IEC 1994 All rights reserved. Unless otherwise specified, no part of this publication may be reprod
11、uced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. ISO/IEC Copyright Office l Case postale 56 l CH-1211 Genke 20 l Switzerland Printed in Switzerland Copyright American National Standards Ins
12、titute Provided by IHS under license with ANSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-ISO/IEC 10918-1:1994(E) Foreword IS0 (the International Organization for Standardization) and IEC (the Inter- national Electrotechnical Commission) form the specialized sy
13、stem for worldwide standardization. National bodies that are members of IS0 or IEC participate in the development of International Standards through technical committees established by the respective organization to deal with particular fields of technical activity. IS0 and IEC technical committees
14、collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in liaison with IS0 and IEC, also take part in the work. In the field of information technology, IS0 and IEC have established a joint technical committee ISO/lEC JTC 1. Draft International
15、 Standards adopted by the joint technical committee 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. International Standard ISO/lEC 10918- 1 was prepared by Joint Technical Com- mittee ISO/
16、lEC JTC 1, Informafion technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information, in collaboration with the CCITT. The identical text is published as CCITT Recommendation T.81. ISO/lEC 10918 consists of the following parts, under the general title Information te
17、chnology - Digital compression and coding of continuous-tone still images: - Part I : Requirements and guidelines - Part 2: Compliance testing Annexes A, B, C, D, E, F, G, H and J form an integral part of this part of ISO/lEC 10918. Annexes K, L and M are for information only. Patents During the pre
18、paration of this part of ISO/IEC 10918, information was gathered on patents upon which application of the standard might depend. Relevant patents were identified as belonging to the patent holders listed in annex L. However, ISO/lEC cannot give authoritative or comprehensive information about eviden
19、ce, validity or scope of patent and like rights. The patent holders have stated that licences will be granted under reasonable terms. Communications on this subject should be addressed to the patent holders (see annex L). . . . 111 Copyright American National Standards Institute Provided by IHS unde
20、r license with ANSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-ISOllEC 10918-1:1994(E) Introduction This part of ISO/IEC 10918 was prepared by CCIlT Study Group VIII and the Joint Photographic Experts Group (JPEG) of ISO/IEC JTC l/SC 29/WG 10. This Experts Grou
21、p was formed in 1986 to establish a standard for the sequential progressive encoding of continuous-tone grayscale and colour images. This part of ISO/IEC 10918 sets out requirements and implementation guidelines for continuous-tone still image encoding and decoding processes, and for the coded repre
22、sentation of compressed image data for interchange between applications. These processes and representations are intended to be generic, that is, to be applicable to a broad range of applications for colour and grayscale still images within communications and computer systems. ISO/IEC 10918-2 sets o
23、ut tests for determining whether implementations comply with the requirements for the various encoding and decoding processes specified in this part of ISO/IFX 10918. The requirements which these processes must satisfy to be useful for specific image communications applications such as facsimile, Vi
24、deotex and audiographic conferencing are defined in CCITT Recommendation T.80. The intent is that the generic processes of Recommendation T.80 will be incorporated into the various CCITT Recommendations for terminal equipment for these applications. In addition to the applications addressed by the C
25、CITT and ISO/IEC, the JPEG committee has developed a compression standard to meet the needs of other applications as well, including desktop publishing, graphic arts, medical imaging and scientific imaging. This Specification aims to follow the guidelines of CCITT and ISO/IEC JTC 1 on Rules for pres
26、entation of CCllT 1 ISOIIEC common text. iv Copyright American National Standards Institute Provided by IHS under license with ANSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-ISO/IEC 1091 - specifies processes for converting compressed image data to reconstruct
27、ed image data: - gives guidance on how to implement these processes in practice; - specifies coded representations for compressed image data NOTE - This Specification does not specify a complete wded image representation. Such representations may include certain parameters, such as aspect ratio, com
28、ponent sample registration, and colour space designation, which are application- dependent. 2 Normative references The following CCITI Recommendations and International Standards contain provisions which, through reference in this text, constitute provisions of this CCITI Recommendation I Internatio
29、nal Standard. At the time of publication, the editions indicated were valid. All Recommendations and Standards are subject to revision, and parties to agreements based on this CCITT Recommendation I International Standard are encouraged to investigate the possibility of applying the most recent edit
30、ion of the Recommendations and Standards listed below. Members of IEC and IS0 maintain registers of currently valid International Standards. The CCITT Secretariat maintains a list of currently valid CCITT Recommendations. - CCIlT Recommendation T-80 (1992), Common components for image compression an
31、d communication - Basic principles. 3 Definitions, abbreviations and symbois 3.1 Definitions and abbreviations For the purposes of this Specification, the following definitions apply. 3.1.1 abbreviated format: A representation of compressed image data which is missing some or all of the table specif
32、ications required for decoding, or a representation of table-specification data without frame headers, scan headers, and entropy-coded segments. 3.1.2 AC coefficient: Any DCT coeffkient for which the frequency is not zero in at least one dimension. 3.13 (adaptive) (binary) arithmetic decoding: An en
33、tropy decoding procedure which recovers the sequence of symbols from the sequence of bits produced by the arithmetic encoder. 3.1.4 (adaptive) (binary) arithmetic encoding: An entropy encoding procedure which codes by means of a recursive subdivision of the probability of the sequence of symbols cod
34、ed up to that point. 3.1.5 application environment: The standards for data representation, communication, or storage which have been established for a particular application. CCITT Rec. T.81(1992 E) 1 Copyright American National Standards Institute Provided by IHS under license with ANSINot for Resa
35、leNo reproduction or networking permitted without license from IHS-,-,-ISOAEC lo!W a sample in lossless processes. 2 CClTT Rec. T DCT: Either the forward discrete cosine transform or the inverse discrete cosine transform. 3.1.48 downsamplhg (filter): A procedure by which the spatial resolution of an
36、 image is reduced (in hierarchical mode coding). 3.1.49 encoder: An embodiient of an encoding process. 3.150 encoding process: A process which takes as its input a continuous-tone image and outputs compressed image data. 3.1.51 entropy-coded (data) segment: An independently de FDCIr A mathematical t
37、ransformation using cosine basis functions which converts a block of samples into a corresponding block of original DCT coefficients. CClTI Rec. T IDCX A mathematical transformation using cosine basis functions which converts a block of dequantized DCX coefficients into a corresponding block of samp
38、les. 3.1.78 Joint Photographic Experts Group; JPEG: The informal name of the committee which created this Specification. The “joint” comes from the CClTI and ISO/IEC collaboration. 3.1.79 latent OU: Output of the arithmetic encoder which is held, pending resolution of carry-over (in arithmetic codin
39、g). 3.1.80 less probable symbol; LPS: For a binary decision, the decision value which has the smaller probability. 3.111 level shift: A procedure used by DCT-based encoders and decoders whereby each input sample is either converted from an unsigned representation to a twos complement representation
40、or from a twos complement representation to an unsigned representation. 4 CClTT Rec. T.81(1992 E) Copyright American National Standards Institute Provided by IHS under license with ANSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-ISOIIEC 10918-1:1994(E) 3.1.82 l
41、ossless: A descriptive term for encoding and decoding processes and procedures in which the output of the decoding procedure(s) is identical to tbe input to the encoding procedure(s). 3.1.83 iossless coding: The mode of operation which refers to any one of the coding processes defined in this Specif
42、ication in which all of the procedures are lossless (see Annex H). 3.1J4 lossy: A descriptive term for encoding and decoding processes which are not lossless. 3.1.85 marker: A two-byte code in which the first byte is hexadecimal FF (XFF) and the second byte is a value between 1 and hexadecimal FE (X
43、FE). 3.1.86 marker segment: A marker and associated set of parameters. 3.1.87 MC MCU: The smallest group of data units that is coded. 3.1.89 modes (of operation): The four main categories of image coding processes defined in this Specification. 3.1.90 more probable symbol; MIS: For a binary decision
44、, the decision value which has the larger probability. 3.1.91 non-differential frame: The fast frame for any components in a hierarchical encoder or decoder. The components are encoded or decoded without subtraction from reference components. The term refers also to any frame in modes other than the
45、 hierarchical mode. 3.1.92 non-interleaved: The descriptive term applied to the data unit processing sequence when the scan has only one component. 3.1.93 parameters: Fixed length integers 4, 8 or 16 bits in length, used in the compressed data formats. 3.1.94 point transform: Scaling of a sample or
46、DCT coefficient. 3.1.95 precision: Number of bits allocated to a particular sample or DCT coefficient. 3.1.96 predictor: A linear combination of previously reconstructed values (in lossless mode coding). 3.1.97 probabiiity estimation state machine: An interlinked table of probability values and indi
47、ces which is used to estimate the probability of the LPS (in arithmetic coding). 3.1.98 probability interval: The probability of a particular sequence of binary decisions within the ordered set of all possible sequences (in arithmetic coding). 3.1.99 (probability) sub-interval: A portion of a probab
48、ility interval allocated to either of the two possible binary decision values (in arithmetic coding). 3.1.100 procedure: A set of steps which accomplishes one of the tasks which comprise an encoding or decoding proC%TSS. 3.1.101 process: See coding process. 3.1.102 progressive (coding): One of the D
49、CT-based processes defined in this Specification in which each scan typically improves the quality of the reconstructed image. 3.1.103 progressive DCT-based: The mode of operation which refers to any one of the processes defined in Annex G. 3.1.104 quantization table: The set of 64 quantization values used to quantize the DCT coefficients. 3.1.105 quantization value: An integer value used in the quantization procedure. 3.1.106 quantize: The act of perfor
