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1、 ICS 35.040 Ref. No. ISO/IEC 15444-2:2004/Cor.3:2005(E) ISO/IEC 2005 All rights reserved Published in Switzerland INTERNATIONAL STANDARD ISO/IEC 15444-2:2004 TECHNICAL CORRIGENDUM 3 Published 2005-06-15 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION ORGANISATION INTERNATIONALE DE NORMALISATION INTER
2、NATIONAL ELECTROTECHNICAL COMMISSION COMMISSION LECTROTECHNIQUE INTERNATIONALE Information technology JPEG 2000 image coding system: Extensions TECHNICAL CORRIGENDUM 3 Technologies de linformation Systme de codage dimages JPEG 2000: Extensions RECTIFICATIF TECHNIQUE 3 Technical Corrigendum 3 to ISO/
3、IEC 15444-2:2004 was prepared by Joint Technical Committee ISO/IEC JTC 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(2002)/Cor.3.(01/2005). -,-,- -,-,- I
4、TU-T Rec. T.801 (2002)/Cor.3 (01/2005) 1 INTERNATIONAL STANDARD ITU-T RECOMMENDATION Information technology JPEG 2000 image coding system: Extensions Technical Corrigendum 3 1) Clause M.5.1 Add a new subclause to clause M.5.1 (Mapping codestreams to compositing layers): M.5.1.3 Establishing a sequen
5、ce order for codestreams A sequence order for codestreams is required for the subsequent ordering of compositing layers and in particular for the case where one or more compositing layers comprises more than one codestream. Codestreams are assigned a sequence order equal to their position in the fil
6、e, starting with zero. In the case where a Fragment Table box is used, the Fragment Table box is considered equivalent to a Contiguous Codestream box for the purpose of establishing a codestream sequence order for the referenced codestream. 2) Clause M.5.1.1 Amend paragraph 2 of clause M.5.1.1 (Esta
7、blishing a sequence order for compositing layers) as follows: If a Component Registration box is present in any Compositing Layer Header box, then there shall be one Component Registration boxCompositing layer header box infor every Compositing Layer Header box in the file, each containing at least
8、one Component Registration box. In this case, the order of compositing layers is given by the sequence order of compositing layer header boxes in the file. 3) Clause M.5.3.2.1 Amend the text in the second bullet of clause M.5.3.2.1 (Special cases of life and persistence) as follows: When PERSIST is
9、true and LIFE is zero then this instruction should be executed together with the next instruction. In practice this combination may occur for a sequence of more than two instructions and shall place the reader into a frame composition mode. This mode is exited when an instruction with non- zero PERS
10、IST LIFE is encountered or when the end of the animation is reached. The set of instructions executed whilst in frame composition mode is referred to as a frame composition sequence. In frame composition mode, a virtual compositing layer is created (off-screen) by executing the instructions in the f
11、rame definition sequence. The PERSIST and LIFE parameters for the closing instruction of a frame definition are applied to the virtual compositing layer as a whole. This mode permits multi-sprite animationThat is, upon close of frame composition mode, all of the compositing layers involved in the fr
12、ame composition sequence acquire the PERSIST and LIFE values of the closing frame in the sequence. ISO/IEC 15444-2:2004/Cor.3:2005 (E) -,-,- 2 ITU-T Rec. T.801 (2002)/Cor.3 (01/2005) 4) Clause M.11.1 a) Amend the SFi field definition of clause M.11.1 (Reader Requirements box) as follows: SFi: Standa
13、rd flag. This field specifies a standard feature flag. The number of SFi fields shall be equal to the value of the NSF field. This field is encoded as a 2-byte big endian unsigned integer. Legal values of this field are shown in Table M.14 Legal values of this field are specified in Table M.14 and i
14、n extensions to this standard. b) Add a new row to Table M.14 (Legal values of the SFi field) defining Value 70: Table M.14 Legal values of the SFi field Value Meaning 1 Codestream contains no extensions 65 Compositing layers have different colour spaces 66 Compositing layers have different metadata
15、 70 Compositing layer uses sYCC enumerated colour space 5) Clause M.11.5 Amend the text in paragraph 2 of clause M.11.5 (JP2 Header box (superbox) as follows: Also, if the codestream isJP2 Header box specified by the JP2 Header boxdefault information for any codestreams, then the semantic relationsh
16、ip of the Image Header box and Bits Per Component box contained within the JP2 Header box shall follow the rules defined in M.11.5.1 and M.11.5.2 respectively. 6) Clause M.11.5.1 Replace the entire definition of the IPR field in clause M.11.5.1 (Image Header box) as follows: IPR: Intellectual Proper
17、ty. The value of this field is identical to that defined for the JP2 file format.This parameter indicates whether this JPX file contains intellectual property rights information that is associated with the codestream or codestreams described by this Image Header box. If the value of this field is 0,
18、 those codestreams do not have associated rights information. If the value is 1, then those codestreams do have associated rights information. Other values are reserved. 7) Clause M.11.7.7 Amend clause M.11.7.7 as follows: M.11.7.7 Codestream Registration box When combining multiple codestreams to c
19、reate a single compositing layer, it is important that the reference grids of those codestreams be properly registered to ensure the registration of the individual samples from the multiple components. This box specifies how those codestreams shall be registered when rendering the layer. A Compositi
20、ng Layer Header box shall contain zero or one Codestream Registration boxes, and Codestream Registration boxes shall be found in no other locations in the file; a Codestream Registration box shall not be placed into the JP2 Header box to specify a default registration. If any Compositing Layer Heade
21、r box contains a Codestream Registration box, then every Compositing Layer Header box shall contain a Codestream Registration box. If this Compositing Layer Header box does not contain a Codestream Registration box, then the compositing layer shall be represented by one and only one codestream. ISO/
22、IEC 15444-2:2004/Cor.3:2005 (E) -,-,- ITU-T Rec. T.801 (2002)/Cor.3 (01/2005) 3 If codestream registration is not specified for a particular compositing layer, then the codestreams in that compositing layer shall be aligned by directly aligning their reference grids at both (0,0) and (1,1). If a Cod
23、estream Registration box exists, then the default display resolution (specified within a Resolution box with the same Compositing Layer Header box) applies to the compositing layer registration grid. This registration is specified with respect to an independent compositing layer registration grid. T
24、he type of the Codestream Registration box shall be creg (0x6372 6567). The contents of this box shall be as follows: T.801_FM-23 CDNn CDN0XSYS XR0 YR0 XO0 YO0 XRn YRn XOn YOn Figure M.23 Organization of the contents of a Codestream Registration box The fields of the codestream registration box may
25、be interpreted in the context of the following equations defining the scaling factors RXi and RYi of the ith codestream in x and y: RXi = XRi / XS RYi = YRi / YS and the offsets OXi and OYi of the ith codestream in x and y: OXi = XOi / XS OYi = YOi / YS on the compositing layer registration grid. Th
26、e overall area of the registration grid is defined to be the intersection of the areas covered by the scaled and offset component codestreams grown out as required to the nearest whole integer registration grid point. The requirement that XOi XS and YOi YS ensures that this intersected area always i
27、ncludes the origin (0,0) of the compositing layer registration grid. If a Codestream Registration box exists, then the default display resolution (specified within a Resolution box with the same Compositing Layer Header box) applies to the compositing layer after all components have been rescaled an
28、d registered. XS: Horizontal grid size. This field specifiesdefines the number of horizontal fractional grid points from (0, 0) to (1, 0) on the compositing layer registration grid. These fractional grid points are used to measure the distance between the reference grids of the individual codestream
29、s. This field is encoded as a 2-byte unsigned integer. YS: Vertical grid size. This field specifiesdefines the number of vertical fractional grid points from (0, 0) to (0, 1) on the compositing layer registration grid. These fractional grid points are used to measure the distance between the referen
30、ce grids of the individual codestreams. This field is encoded as a 2-byte unsigned integer. CDNi: Codestream number. This field specifies the number of the codestream for this registration value. XRi: Horizontal resolution. This field specifies the horizontal distance between points on the reference
31、 grid of the codestream specified by the CDNi parameter, measured in the number of fractional points on the compositing layer registration grid. This field effectively specifies the horizontal scaling needed to match the codestreams reference grid with the compositing layer registration grid. This f
32、ield is encoded as a 1-byte unsigned integer. YRi: Vertical resolution. This field specifies the vertical distance between points on the reference grid of the codestream specified by the CDNi parameter, measured in the number of fractional points on the compositing layer registration grid. This fiel
33、d effectively specifies the vertical scaling needed to match the codestreams reference grid with the compositing layer registration grid. This field is encoded as a 1-byte unsigned integer. XOi: Horizontal offset. This field specifies the horizontal distance (to the right) from the origin of the com
34、positing layer registration grid to the centre of the top left point on the reference grid of the codestream specified by the CDNi parameter to the centre of the top left point on the compositing layer registration grid This field is encoded as a 1-byte unsigned integer. Its value must be strictly l
35、ess than the value of XS. ISO/IEC 15444-2:2004/Cor.3:2005 (E) -,-,- 4 ITU-T Rec. T.801 (2002)/Cor.3 (01/2005) YOi: Vertical offset. This field specifies the vertical distance (downward) from the origin of the compositing layer registration grid to the centre of the top left point on the reference gr
36、id of the codestream specified by the CDNi parameter to the centre of the top left point on the compositing layer registration grid This field is encoded as a 1-byte unsigned integer. Its value must be strictly less than the value of YS. Table M.35 Format of the contents of the Codestream Registrati
37、on box Field name Size (bits) Value XS 16 0-65 535 YS 16 0-65 535 CDNi 16 0-65 535 XRi 8 0-255 YRi 8 0-255 XOi 8 0-255 YOi 8 0-255 8) Clause M.11.10.1 Amend clause M.11.10.1 as follows: M.11.10.1 Composition Options box The Composition Options box specifies parameters that apply to the composition o
38、r animation as a whole. The Composition Options box shall be the first box in the Composition box and a Composition Options box shall not be found in any other location in the file. The type of the Composition Options box shall be copt (0x636F 7074) and contents of the box shall have the following f
39、ormat: T.801_FM-25 HEIGHTWIDTH LOOP T.801_FM-25 HEIGHTWIDTH LOOP Figure M.25 Organization of the contents of a Composition Options box HEIGHT: Rendered result height. This field specifies the height, in samples, of the final rendered result. The resolution of this value is optionally defined in the
40、Default Display Resolution box in the JP2 Header box. This field is encoded as a 4-byte unsigned integer. WIDTH: Rendered result width. This field specifies the width, in samples, of the final rendered result. The resolution of this value is optionally defined in the Default Display Resolution box i
41、n the JP2 Header box. This field is encoded as a 4-byte unsigned integer. GREPTLOOP: Looping count. This field specifies the number of times to fully execute the display instructions.Global Repetition. This field specifies the number of times to fully repeat the display instructions, after executing
42、 the display instructions the first time. For a GREPT value of zero this means the entire set of instructions in the comp box is executed once. A value of 255 indicates that the reader should repeat the entire set of instructions indefinitely. Prior to each execution of the instruction set, the disp
43、lay area shall be restored to its original state and all instructions composition layer association reset. Each loop execution should be visually equivalent to redisplaying the composition from scratch. This field is encoded as a 1-byte unsigned integer. CREPT ISO/IEC 15444-2:2004/Cor.3:2005 (E) -,-
44、,- ITU-T Rec. T.801 (2002)/Cor.3 (01/2005) 5 Table M.37 Format of the contents of the Composition Options box Parameter Size (bits) Value HEIGHT 32 1-2321 WIDTH 32 1-2321 LOOP GREPT 8 0-255 9) Clause M.11.10.2 Amend the description of the REPT field in clause M.11.10.2 as follows: REPT: Repetition.
45、This field specifies the number of times to repeat this particular set of instructions after executing the instruction set the first time. The instructions are always executed at least once (REPT is zero) and the instructions may apply to different compositing layers on each repetition as determined
46、 by the Next-use field of the instructions. This field is encoded as a 2-byte big endian unsigned integer. A value of 65 535 indicates to repeat the instruction indefinitely. 10) Clause M.11.10.2.1 Amend the description of the NEXT-USE field in clause M.11.10.2.1 as follows: NEXT-USE: Number of inst
47、ructions before reuse. This field specifies the number of instructions that shall be executed before reusing the current compositing layer. This field allows readers to simply optimize their caching strategy. A value of zero implies that the current image shall not be reused for any ensuing instruct
48、ions, notwithstanding the execution of a global loop as a result of a non-zero value of the LOOPGREPT parameter in the Composition Options box. A value of one (1) implies that the current compositing layer will be used with the next instruction and so on. The compositioncompositing layer passed on for reuse in this manner must be the original compositing layer, prior to any cropping or scaling indicated by the current instruction. If this field is not prese