1、INCITS/ISO/IEC 15444-2:2004/Amd.2-20062008 (ISO/IEC 15444-2:2004/Amd.2:006 , IDT) Information technology JPEG 2000 image codingsystem: Extensions AMENDMENT 2: Extended capabilitiesINCITS/ISO/IEC 15444-2:2004/Amd.2-20062008(ISO/IEC 15444-2:2004/Amd.2:2006, IDT)INCITS/ISO/IEC 15444-2:2004/Amd.2-200620
2、08ii ITIC 2008 All rights reserved PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the
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5、 at the address given below. Adopted by INCITS (InterNational Committee for Information Technology Standards) as an American National Standard. Date of ANSI Approval: 11/12/2008 Published by American National Standards Institute, 25 West 43rd Street, New York, New York 10036 Copyright 2008 by Inform
6、ation 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), and Information Technology Industry Counci
7、l (ITI). Not for resale. No part of this publication may be reproduced in any form, including an electronic retrieval system, without the 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 Uni
8、ted States of America ITIC 2008 All rights reserved iiiForeword ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC participate in th
9、e development of International Standards through technical committees established by the respective organization to deal with particular fields of technical activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international organizations, governmental and non-go
10、vernmental, in liaison with ISO and IEC, also take part in the work. In the field of information technology, ISO and IEC have established a joint 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 tas
11、k of the joint technical committee is to prepare International Standards. Draft International 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
12、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 not be held responsible for identifying any or all such patent rights. Amendment 2 to ISO/IEC 15444-2:2005 was prepared by Joint Technical Committee ISO/IEC J
13、TC 1, Information technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information, in collaboration with ITU-T. The identical text is published as ITU-T Rec.T.801/Amd.2. INCITS/ISO/IEC 15444-2:2004/Amd.2-20062008 iv ITIC 2008 All rights reservedIntroduction The JPEG 2
14、000 specification is structured in several parts: Part 1 is defined in ITU-T Rec. T.800 | ISO/IEC 15444-1 (“Core coding system“). Part 2 is defined in ITU-T Rec. T.801 | ISO/IEC 15444-2 (“Extensions“). Part 3 is defined in ITU-T Rec. T.802 | ISO/IEC 15444-3 (“Motion JPEG 2000“). Part 4 is defined in
15、 ITU-T Rec. T.803 | ISO/IEC 15444-4 (“Conformance testing“). Part 5 is defined in ITU-T Rec. T.804 | ISO/IEC 15444-5 (“Reference software“). Part 6 is defined in ISO/IEC 15444-6 (“Compound image file format“). Part 7 has been withdrawn. Part 8 is defined in ISO/IEC 15444-8 (“Secured JPEG format“). P
16、art 9 is defined in ITU-T Rec. T.808 | ISO/IEC 15444-9 (“Interactivity tools, APIs and protocols“). Part 10 is defined in ISO/IEC 15444-10 (“3-D and floating point data“). Part 11 is defined in ISO/IEC 15444-11 (“Wireless“). Part 12 is defined in ISO/IEC 15444-12 (“ISO base media file format“). The
17、need for this amendment arises from a lack of sufficient codespace in the Rsiz capabilities parameter in the SIZ marker segment. The Rsiz parameter contains 16 bits, which are used to signal decoding capabilities required by the encoded codestream. According to Table A.10 of ITU-T Rec. T.800 | ISO/I
18、EC 15444-1, the only values used in Part 1 codestreams are: Rsiz = 0000 0000 0000 00xx where: xx = 00 indicates a generic Part 1 codestream xx = 01 indicates a profile 0 codestream xx = 10 indicates a profile 1 codestream In Table A.2, the first bit of Rsiz is used to indicate the presence of Part 2
19、 features, and the bit values assigned to specific Part 2 capabilities are: Rsiz = 1000 yzzz zzzz zzzz where y = 1 indicates a codestream using Part 2 (precinct-dependent quantization) and bits 6-16 (the z-bits) indicate extensions defined in the Part 2 annexes. In particular, note that there are on
20、ly 3 unused bits (bits #2, 3, and 4) remaining in the Rsiz field. Signalling Part 2 capabilities requires a full bit per capability because Part 2 features can be selected independently (i.e., in arbitrary combinations) by encoders, and this situation can be expected to continue for extensions defin
21、ed in subsequent Parts of the JPEG 2000 family or in future Part 2 amendments. This includes extensions presently under development in JPEG 2000 Parts 8 (JPSEC), 10 (JP3D), and 11 (JPWL), many of which will be used in conjunction with other extensions from different Parts of JPEG 2000. Consequently,
22、 the three remaining unused bits in Rsiz are far from sufficient for signalling future JPEG 2000 codestream capabilities. Rather than forcing future JPEG 2000 extensions to invent their own methods of signalling required codestream capabilities, this amendment defines a unified, scalable, semantical
23、ly flexible framework for capabilities signalling that can be used by all future JPEG 2000 Parts and amendments. Moreover, it is fully backwards-compatible with the present capabilities signalling employed in the Rsiz parameter. The key idea is to define a new variable-length Part 2 marker segment (
24、the CAP marker segment) that indicates the Parts and the specific extended capabilities used to encode the codestream in question. Use of the CAP marker segment is indicated by the second-most-significant bit in the Rsiz parameter. The second bit in the Rsiz parameter can also optionally be used to
25、indicate that a CAP marker segment is used. To a baseline decoder, this will appear as the indication of an unknown capability, which generally prevents the decoder from further decoding the codestream. INCITS/ISO/IEC 15444-2:2004/Amd.2-20062008ITU-T Rec. T.801 (2002)/Amd.2 (05/2005) 1 INTERNATIONAL
26、 STANDARD ITU-T RECOMMENDATION Information technology JPEG 2000 image coding system: Extensions Amendment 2 Extended capabilities marker segment 1) Table A.2 In Table A.2: replace all occurrences of “1000” in the four most significant bits of the index values with “1x00”; and add the following entri
27、es immediately preceding the entry describing variable DC offset capability: 0100 0000 0000 00xx Capabilities specified in ITU-T Rec. T.800 | ISO/IEC 15444-1 and at least one extended capability indicated in the CAP marker segment 1100 xxxx xxxx xxxx Extended capabilities defined in this Recommendat
28、ion | International Standard as indicated in this parameter, and at least one other extended capability indicated in the CAP marker segment so that Table A.2 will now read: Value (bits) MSB LSB Capability 0000 0000 0000 0000 Capabilities specified in ITU-T Rec. T.800 | ISO/IEC 15444-1 only 1x000 xxx
29、x xxxx xxxx At least one of the extended capabilities specified in this Recommendation | International Standard is present 0100 0000 0000 00xx Capabilities specified in ITU-T Rec. T.800 | ISO/IEC 15444-1 and at least one extended capability indicated in the CAP marker segment 1100 xxxx xxxx xxxx Ext
30、ended capabilities defined in this Recommendation | International Standard as indicated in this parameter, and at least one other extended capability indicated in the CAP marker segment 1x000 xxx0 xxxx xxx1 Variable DC offset capability is required to decode this codestreama) b)1x000 xxxx xxxx xx1x
31、Variable scalar quantization capability is required to decode this codestreama)1x000 xxxx xxxx x1xx Trellis coded quantization capability is useful to decode this codestreamc)1x000 xxxx xxxx 1xxx Visual masking capability is useful to decode this codestreamc)1x000 xxxx xxx1 xxxx Single sample overla
32、p capability is required to decode this codestreama)1x000 xxxx xx1x xxxx Arbitrary decomposition style capability is required to decode this codestreama)1x000 xxxx x1xx xxxx Arbitrary transformation kernel capability is required to decode this codestreama)1x000 xxxx 1xxx xxxx Whole sample symmetric
33、transformation kernel capability is required to decode this codestreama)1x000 xxx1 xxxx xxxx Multiple component transformation capability is required to decode this codestreama)1x000 xx1x xxxx xxxx Non-linear point transformation capability is useful to decode this codestreamc)1x000 x1xx xxxx xxxx A
34、rbitrary shaped region of interest capability is required to decode this codestreama)1x000 1xxx xxxx xxxx Precinct-dependent quantization is required to decode this codestreama)All other values reserved a)“Required to decode“ implies that no useful data or image can be reconstructed without the use
35、of this capability. b)Shall not be used with the multiple component transformation. c)“Useful to decode“ implies that use of this capability would improve the quality of the reconstructed data or image; however, the data or image may be decoded without its use. INCITS/ISO/IEC 15444-2:2004/Amd.2-2006
36、2008 2 ITU-T Rec. T.801 (2002)/Amd.2 (05/2005) 2) New clause A.3.13 Add the following A.3.13: A.3.13 Extended capabilities (CAP) Function: Signals that extended capabilities were used to create (and are recommended or required to decode) a codestream. Usage: Optional. If present, must be included an
37、ywhere in the main header after the SIZ marker segment. The second-most-significant bit in Rsiz may optionally be set to 1 to indicate the presence of the CAP marker segment. Length: Variable. CAP Lcap Pcap CcapiCcapn Figure A.13 Extended capabilities syntax CAP: Marker code. Table A.49 shows the si
38、ze and values of the symbol and parameters for the extended capabilities marker segment. Lcap: Length of the CAP marker segment (not including the marker). Length is given by the following formula: Lcap = 6 + 2n bytes where n is the number of 1-bits occurring in Pcap. Pcap: 32-bit field indicating t
39、he Parts containing extended capabilities that are used to encode the image. A value of 1 in the kth-most-significant bit of Pcap indicates the use of capabilities from Part k (ISO/IEC 15444-k). The first non-zero bit in Pcap corresponds to the first Ccapifield (i = 1); the second non-zero bit in Pc
40、ap corresponds to the second Ccapifield (i = 2), etc. Table A.50 shows the usage of the Pcap parameter. Ccapi: 16-bit field indicating capabilities specified in Part piwhere bit #pi is the ith non-zero bit in Pcap. If p1= 2, the bits in Ccap1 shall indicate capabilities defined in Part 2 amendments;
41、 the MSB of Rsiz may be set to the value 1 in this case. For other Parts, the bits in Ccapi may be used to indicate capabilities defined in Part pi. The precise meaning of the bits in Ccapi shall be specified in Part pi(ISO/IEC 15444-pi). Table A.49 Extended capabilities parameter values Parameter S
42、ize (bits) Value CAP 16 0xFF50 Lcap 16 80-560 Pcap 32 See Table A.50 Ccapi16 Value and meaning specified in ISO/IEC 15444-k, where the ith non-zero bit in Pcap occurs in its kth most significant bit Table A.50 Part parameter values for the Pcap parameter Values (bits) MSB LSB Part parameter 1xxx xxx
43、x xxxx xxxx xxxx xxxx xxxx xxxx Extended capabilities from ISO/IEC 15444-1 were used to encode the image x1xx xxxx xxxx xxxx xxxx xxxx xxxx xxxx Extended capabilities from ISO/IEC 15444-2 were used to encode the image xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxx1 Extended capabilities from ISO/IEC 15444-3
44、2 were used to encode the image INCITS/ISO/IEC 15444-2:2004/Amd.2-20062008ITU-T Rec. T.801 (2002)/Amd.2 (05/2005) 3 Guidance on usage (informative): Encoders that wish to induce baseline JPEG-2000 (Part 1) decoders to attempt best-effort decoding of a codestream containing non-Part 1 features may el
45、ect not to use the second-most-significant bit in Rsiz to signal the presence of the CAP marker segment. According to clause A.1 of ITU-T Rec. T.800 | ISO/IEC 15444-1, decoder implementations are supposed to deal with unrecognized marker segments by using the length parameter to discard the marker s
46、egment. Because of this possibility, decoders that recognize any of the capabilities that would be indicated in a CAP marker segment may choose to parse for the CAP marker segment in all JPEG 2000 codestreams, regardless of the value of the second Rsiz bit. Encoders should facilitate this parsing by
47、 placing the CAP marker segment as close as possible to the front of the main header. It is recommended that the CAP marker segment always appear before any other marker segments that support extended capabilities indicated in the CAP marker segment, so that such capabilities will have been indicate
48、d to the decoder prior to encountering any related marker segments. Encoders that wish to deter baseline decoders from attempting to decode a codestream that truly requires capabilities indicated in the CAP marker segment should set the second Rsiz bit to 1. INCITS/ISO/IEC 15444-2:2004/Amd.2-20062008 ICS 35.040 Price based on 3 pages ITIC 2008 All rights reserved INCITS/ISO/IEC 15444-2:2004/Amd.2-20062008
