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author | Thomas Voss <mail@thomasvoss.com> | 2024-11-27 20:54:24 +0100 |
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committer | Thomas Voss <mail@thomasvoss.com> | 2024-11-27 20:54:24 +0100 |
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tree | e3989f47a7994642eb325063d46e8f08ffa681dc /doc/rfc/rfc3745.txt | |
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diff --git a/doc/rfc/rfc3745.txt b/doc/rfc/rfc3745.txt new file mode 100644 index 0000000..94d641c --- /dev/null +++ b/doc/rfc/rfc3745.txt @@ -0,0 +1,787 @@ + + + + + + +Network Working Group D. Singer +Request for Comments: 3745 Apple Computer +Category: Standards Track R. Clark + Elysium Ltd + D. Lee + Yahoo Inc. + April 2004 + + + MIME Type Registrations for JPEG 2000 (ISO/IEC 15444) + +Status of this Memo + + This document specifies an Internet standards track protocol for the + Internet community, and requests discussion and suggestions for + improvements. Please refer to the current edition of the "Internet + Official Protocol Standards" (STD 1) for the standardization state + and status of this protocol. Distribution of this memo is unlimited. + +Copyright Notice + + Copyright (C) The Internet Society (2004). All Rights Reserved. + +Abstract + + This document serves to register and document the standard MIME types + associated with the ISO/IEC 15444 standards, commonly known as JPEG + 2000 (Joint Photographic Experts Group). + +1. Introduction + + This document describes the registration of the MIME [MIME1] sub- + types image/jp2, video/mj2, image/jpx, and image/jpm. The image + encoding is defined by [ISO-JPEG2000-1]. + + The still image file format to which this document refers is defined + in Annex I of [ISO-JPEG2000-1]. Note that a file format is optional + in [ISO-JPEG2000-1], but mandatory for the MIME sub-type. This + document is not related to the definition of the MIME sub-type + image/jpeg, which is partly defined by [ISO-JPEG-1], and partly by + the file format specification defined in [JFIF]. + + JPEG 2000 is a new standard, intended to create a image coding system + for many types of still images (bi-level, gray-level, color, multi- + component) with different characteristics (natural images, + scientific, medical, remote sensing, imagery, text, rendered + graphics, etc.) allowing different imaging models (client/server, + real-time transmission, image library archival, limited buffer and + + + +Singer, et al. Standards Track [Page 1] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + + bandwidth resources, etc.) within a unified system. This coding + system is intended to provide low bit-rate operation with rate- + distortion and subjective image quality performance superior to + existing standards, without sacrificing performance at other points + in the rate-distortion spectrum. + + This standard is intended to serve still image compression needs that + are currently not served by the current JPEG standards [ISO-JPEG-1], + [ISO-JPEG-2], [ISO-JPEG-3], and [ISO-JPEG-4], and is intended to + compliment, not replace, the current JPEG standards. JPEG 2000 is a + modern wavelet-based codec that is expected to be widely used for + still images. Its use for motion sequences is expected to be similar + to JPEG: in those environments where only a single codec is + required, and JPEG 2000 is available (e.g., digital still cameras + recording short motion sequences) or where frame-by-frame coding is + desired (no inter-frame coding). + + There is a standard file format for Motion JPEG 2000 sequences. This + file format permits the carriage of audio in addition to the video. + The format is derived from the ISO Base Media File Format as defined + in [ISO-JPEG2000-12]. The visual coder in a Motion JPEG 2000 file is + JPEG 2000. The Motion JPEG 2000 standard is specified in [ISO- + JPEG2000-3]. The ISO Base Media File Format is jointly maintained by + the ISO/IEC JPEG and MPEG committees. The MP4 format is also derived + from the ISO Base Media File Format. + + Therefore, to identify this restricted usage, a new mime type is + desirable. + + This file type is intended always to contain a video sequence, though + simple audio is permitted in addition to the video. Therefore it + falls correctly under the "video" branch of mime types. + + Also within WG1 of ISO there is an effort underway to define a + standard file format for Compound Images. This file format + optionally supports other coding systems, in addition to JPEG 2000, + as needed. + +2. JPEG 2000 Definition + + JPEG 2000 is defined in detail in [ISO-JPEG2000-1]. The + documentation can be obtained from any national standards body or + from ISO at http://www.iso.ch. + + Information as to its latest status, and downloads of the initial + documents and some supporting documentation are available through the + JPEG committee's official Web site at http://www.jpeg.org. + + + + +Singer, et al. Standards Track [Page 2] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + + While a brief scope and feature description is provided in this + section as background information, the reader is directed to the + original JPEG 2000 specification [ISO-JPEG2000-1] to obtain complete + feature and technical details. + +2.1. JPEG 2000 Scope + + JPEG 2000 is used to compress image data that typically comes from + digital cameras, scanners, frame grabbers, complex image capture + devices such as medical or satellite systems, and paint- and photo- + retouching programs. Unlike previous JPEG standards, it includes + information necessary to allow its use as a complete coding + architecture. [ISO-JPEG2000-1] defines a set of lossless (bit- + preserving) and lossy compression methods for coding continuous-tone, + bi-level, gray-scale, or colour digital still images. It therefore: + + - specifies decoding processes for converting compressed image data + to reconstructed image data; + + - specifies a codestream syntax containing information for + interpreting the compressed image data; + + - specifies a file format; + + - provides guidance on encoding processes for converting source + image data to compressed image data; + + - provides guidance on how to implement these processes in practice. + + [ISO-JPEG2000-1] is one of a series of standards which will cover the + full range of facilities the new architecture is intended to offer. + Approval has been given for JPEG to develop the following documents + in addition to [ISO-JPEG2000-1]. + + - Part 2 - Coding extensions [ISO-JPEG2000-2]. This includes a more + comprehensive file format and other extensions to the definitions + in [ISO-JPEG2000-1]. The mime sub-type image/jpx is recommended + to describe files based on this Part, and a separate RFC is + planned to describe this usage and its associated file extensions + of jpf and jpx. + + - Part 3 - Motion JPEG 2000 [ISO-JPEG2000-3]. This provides + definitions of how the standard may be extended for use in + recording time series of JPEG 2000 images with associated metadata + such as audio objects. This document registers the mime sub-type + video/mj2 for motion JPEG 2000, with associated file extensions + mj2 and mjp2. + + + + +Singer, et al. Standards Track [Page 3] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + + - Part 4 - Conformance [ISO-JPEG2000-4]. This deals with testing of + equipment and systems claimed to conform to the JPEG 2000 + standards. + + - Part 5 - Reference software [ISO-JPEG2000-5]. This will provide + developers with a source of publicly available reference software. + Its role is envisaged as similar in concept to that played by the + Independent JPEG Group (IJG) in publicizing the current [ISO- + JPEG-1] standard. + + - Part 6 - Compound Image File Format [ISO-JPEG2000-6]. This + describes a file format used to store compound documents using + JPEG 2000 compression. These may contain scanned images, + synthetic images or both. This work is based on the multi-layer + Mixed Raster Content (MRC) imaging model, defined in ITU-T T.44 | + ISO 16485. The mime sub-type image/jpm is recommended to describe + files based on this Part. + + - Part 7 - Has been withdrawn + + - Part 8 - JPSEC (Security aspects) [ISO-JPEG2000-8]. This provides + standardised tools and solutions in terms of specifications in + order to ensure the security of transaction, protection of + contents (IPR), and protection of technologies (IP), and to allow + applications to generate, consume, and exchange JPEG 2000 Secured + bitstreams. + + - Part 9 - JPIP (Interactive protocols) [ISO-JPEG2000-9]. This + client-server protocol has been designed to exploit JPEG 2000's + flexibility with respect to random access, codestream reordering + and incremental decoding in a networked environment. + + - Part 10 - JP3D (Volumetric imaging) [ISO-JPEG2000-10]. This will + provide extensions of JPEG 2000 for logically rectangular 3- + dimensional data sets with no time component. + + - Part 11 - JPWL (Wireless applications) [ISO-JPEG2000-11]. This + extends the elements in [ISO-JPEG2000-1] with mechanisms for error + protection and correction. + + - Part 12 - ISO Base Media File Format [ISO-JPEG2000-12]. This is + the part of the file format used by JPEG 2000 which is common with + that used within MPEG-4 [ISO-MPEG4]. + + + + + + + + +Singer, et al. Standards Track [Page 4] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + +2.2. JPEG 2000 Features + + Some of the features of JPEG 2000 include: + + - JPEG 2000 is capable of describing bi-level, grayscale, palette- + color, and full-color image data in several color spaces. + + - JPEG 2000 includes a number of compression schemes that allow + developers to choose the best space or time tradeoff for their + applications. + + - JPEG 2000 is designed to be extensible and to evolve gracefully as + new needs arise. + + - JPEG 2000 allows the inclusion of an unlimited amount of private + or special-purpose information within the metadata of its file + format. + + - These are features that JPEG 2000 shares with the definition of + TIFF [RFC-TIFF]. In addition, JPEG 2000 offers: + + - state of the art lossless and lossy compression, based on wavelet + technology, within a single codestream + + - low bit-rate compression performance effective down to below 0.25 + bits per pixel for high resolution gray-scale images + + - large image handling (greater than 64k x 64k pixels) without + tiling + + - single decompression architecture. The current JPEG standard + [ISO-JPEG-1] has 44 modes, many of which are application specific + and not used by the majority of JPEG decoders. + + - features to improve transmission in noisy environments, for + example mobile radio / telephony + + - capability to handle both natural and computer generated imagery + +3. Security Considerations + + JPEG 2000 utilizes a structure that can store image data, and + metadata corresponding to this image data. The fields defined in the + JPEG 2000 standards are of a descriptive nature and provide + information that may be useful to facilitate viewing, rendering and + cataloging of images by a recipient. As such, the fields currently + defined in the JPEG 2000 standards do not in themselves create + additional security risks, since the fields are not used to induce + + + +Singer, et al. Standards Track [Page 5] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + + any particular behavior by the recipient application. It should be + noted that selected metadata fields may encompass information partly + intended to protect the image against unauthorized use or + distribution. In this case the intention is that alteration or + removal of the data in the field would be treated as an offense under + national agreements based World Intellectual Property Organization + (WIPO) treaties. + + JPEG 2000 has an extensible structure, so that it is theoretically + possible that metadata fields could be defined in the future which + could be used to induce particular actions on the part of the + recipient, thus presenting additional security risks, but this type + of capability is currently not supported in the referenced JPEG 2000 + specification. + + Encryption, signing, or authentication of these file formats can use + mechanisms defined in [ISO-JPEG2000-8]. + +4. MIME Types + +4.1. Still Image Registration + + The image/jp2 content-type refers to all of the profiles and + extensions that build on JPEG 2000 [ISO-JPEG2000-1] encoded image + data. The file format is also defined in [ISO-JPEG2000-1], Annex I. + The recommended file suffix is "jp2" + + To: ietf-types@iana.org + Subject: Registration of Standard MIME media type image/jp2 + +MIME media type name: image +MIME subtype name: jp2 +Required parameters: none +Optional parameters: none + It is up to the implementation to + determine the application (if + necessary) and render the image to + the user. +Encoding considerations: files are binary and should be + transmitted in a suitable encoding + without CR/LF conversion, 7-bit + stripping etc.; base64 is a suitable + encoding; +Security considerations: see above +Interoperability considerations: The ability of implementations to + handle all the defined applications + (or profiles within applications) of + JPEG 2000 may not be ubiquitous. As + + + +Singer, et al. Standards Track [Page 6] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + + a result, implementations may decode + and attempt to display the encoded + JPEG 2000 image data only to + determine that the image cannot be + rendered either partially or in full. +Published specification: ISO/IEC 15444-1 defines the JPEG 2000 + codec and the jp2 file format +Applications which use this media type: Imaging, fax, messaging and + multi-media +Additional information: +Magic number(s): 12 byte string: X'0000 000C 6A50 2020 + 0D0A 870A' (for all JPEG-2000 family + files) +File extension(s): jp2 and jpg2 are both declared at + http://www.nist.gov/nics/; jp2 is + preferred +Macintosh File Type Code(s): 'jp2 ' +Person & email address to contact for further information: + JPEG Webmaster - mimesupport@jpeg.org + JPEG Convenor - convenor@jpeg.org + JPEG2000 Editor - J2KEditor@jpeg.org +Intended usage: COMMON +Change controller: JPEG Webmaster + +4.2. Extended Still Image Registration + + The image/jpx content-type refers to all of the profiles and + extensions that build on JPEG 2000 [ISO-JPEG2000-2] encoded image + data. The file format is also defined in [ISO-JPEG2000-2], Annex M. + The recommended file suffix is "jpf" + + To: ietf-types@iana.org + Subject: Registration of Standard MIME media type image/jpx + +MIME media type name: image +MIME subtype name: jpx +Required parameters: none +Optional parameters: none + It is up to the implementation to + determine the application (if + necessary) and render the image to + the user. +Encoding considerations: files are binary and should be + transmitted in a suitable encoding + without CR/LF conversion, 7-bit + stripping etc.; base64 is a suitable + encoding; +Security considerations: see above + + + +Singer, et al. Standards Track [Page 7] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + +Interoperability considerations: The ability of implementations to + handle all the defined applications + (or profiles within applications) of + JPEG 2000 may not be ubiquitous. As + a result, implementations may decode + and attempt to display the encoded + JPEG 2000 image data only to + determine that the image cannot be + rendered either partially or in full. +Published specification: ISO/IEC 15444-2, JPEG 2000 Extensions +Applications which use this media type: Imaging, fax, messaging and + multi-media +Additional information: +Magic number(s): 12 byte string: X'0000 000C 6A50 2020 + 0D0A 870A' (for all JPEG-2000 family + files) +File extension(s): jpf is declared at + http://www.nist.gov/nics/. jpx is + also an acceptable file extension, + although it is not recommended for + files on a desktop computer that are + not directly associated with a MIME + media type +Macintosh File Type Code(s): 'jpx ' +Person & email address to contact for further information: + JPEG Webmaster - mimesupport@jpeg.org + JPEG Convenor - convenor@jpeg.org + JPEG 2000 Editor - J2KEditor@jpeg.org +Intended usage: COMMON +Change controller: JPEG Webmaster + +4.3. Motion Registration + +MIME media type name: video +MIME subtype name: mj2 + +Required parameters: none +Optional parameters: none +Encoding considerations: files are binary and should be + transmitted in a suitable encoding + without CR/LF conversion, 7-bit + stripping etc.; base64 is a suitable + encoding; +Security considerations: see above +Interoperability considerations: A number of interoperating + implementations exist within the + MPEG-4 community with the formats + derived from the ISO Base Media File + + + +Singer, et al. Standards Track [Page 8] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + + Format; and that community has + reference software for reading and + writing the file format. Reference + software for MJP2 is also available. +Published specification: ISO/IEC 15444-3, Motion JPEG 2000 +Applications: Multimedia +Additional information: + +Magic number(s): 12 byte string: X'0000 000C 6A50 2020 + 0D0A 870A' (for all JPEG-2000 family + files) +File extension(s): mj2 and mjp2 are both declared at + http://www.nist.gov/nics/; mj2 is + preferred +Macintosh File Type Code(s): mjp2 is registered with Apple + +Person to contact for info: David Singer, singer@apple.com + +Intended usage: Common + +Author/Change controller: David Singer, MJP2 file format editor + +4.4. Compound Image Registration + + The image/jpm content-type refers to all of the profiles and + extensions that build on JPEG 2000 [ISO-JPEG2000-1] encoded image + data. The file format is also defined in [ISO-JPEG2000-6]. The + recommended file suffix is "jpm" + + To: ietf-types@iana.org + Subject: Registration of Standard MIME media type image/jpm + +MIME media type name: image +MIME subtype name: jpm +Required parameters: none +Optional parameters: none + It is up to the implementation to + determine the application (if + necessary) and render the image to + the user. +Encoding considerations: files are binary and should be + transmitted in a suitable encoding + without CR/LF conversion, 7-bit + stripping etc.; base64 is a suitable + encoding; +Security considerations: see above + + + + + +Singer, et al. Standards Track [Page 9] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + +Interoperability considerations: A number of interoperating + implementations are under development + within the JPEG 2000 community. +Published specification: ISO/IEC 15444-6, JPEG 2000 Compound + Image File Format +Applications: Imaging, fax, messaging, scanning +Additional information: +Magic number(s): 12 byte string: X'0000 000C 6A50 2020 + 0D0A 870A' (for all JPEG-2000 family + files) +File extension(s): jpm and jpgm are both declared at + http://www.nist.gov/nics/; jpm is + preferred +Macintosh File Type Code(s): 'jpm ' +Person & email address to contact for further information: + JPEG Webmaster - mimesupport@jpeg.org + JPEG Convenor - convenor@jpeg.org + JPEG 2000 Editor - J2KEditor@jpeg.org +Intended usage: COMMON +Change controller: JPEG Webmaster + +5. IANA Considerations + + This document registers the MIME types image/jp2, image/jpx, + video/mj2, and image/jpm, defined above. + +6. Acknowledgments + + This document has benefited greatly by contributions from many + people, including Eric Edwards and Takahiro Fukuhara. Their + contribution is gratefully acknowledged. + +6. References + +6.1. Normative References + + [ISO-JPEG2000-1] ITU-T Recommendation T.800 | ISO/IEC 15444-1. + International Organization for Standardization, + "JPEG 2000 Image Coding System: Core Coding + System". + + [ISO-JPEG2000-2] International Organization for Standardization, + "JPEG 2000 Image Coding System: Extensions", IS + 15444-2. + + [ISO-JPEG2000-3] International Organization for Standardization, + "Motion JPEG 2000", IS 15444-3. + + + + +Singer, et al. Standards Track [Page 10] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + + [ISO-JPEG2000-6] International Organization for Standardization, + "JPEG 2000 Image Coding System: Compound Image File + Format", IS 15444-6. + + [ISO-JPEG2000-12] International Organization for Standardization, + "JPEG 2000 Image Coding System: ISO base media file + format", IS 15444-12 (technically identical to + ISO/IEC 14496-12. + + [MIME1] Freed, N. and n. Borenstein, "Multipurpose Internet + Mail Extensions [MIME] Part One: Format of Internet + Message Bodies", RFC 2045, November 1996. + +6.2. Informative References + + [ISO-JPEG2000-4] International Organization for Standardization, + "JPEG 2000 Image Coding System: Conformance + Testing", IS 15444-4. + + [ISO-JPEG2000-5] International Organization for Standardization, + "JPEG 2000 Image Coding System: Reference + Software", IS 15444-5. + + [ISO-JPEG2000-8] International Organization for Standardization, + "JPEG 2000 Image Coding System: JPSEC - Secure JPEG + 2000", IS 15444-8. + + [ISO-JPEG2000-9] International Organization for Standardization, + "JPEG 2000 Image Coding System: JPIP - + Interactivity tools, APIs and protocols", IS + 15444-9. + + [ISO-JPEG2000-10] International Organization for Standardization, + "JPEG 2000 Image Coding System: JP3D - 3-D and + floating point data", IS 15444-10. + + [ISO-JPEG2000-11] International Organization for Standardization, + "JPEG 2000 Image Coding System: JPWL - Wireless", + IS 15444-11. + + [ISO-JPEG-1] ITU-T Recommendation T.81 | ISO/IEC 10918-1:1994, + Information technology - Digital compression and + coding of continuous-tone still images: + Requirements and guidelines. + + + + + + + +Singer, et al. Standards Track [Page 11] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + + [ISO-JPEG-2] ITU-T Recommendation T.83 | ISO/IEC 10918-2:1995, + Information technology - Digital compression and + coding of continuous-tone still images: Compliance + testing. + + [ISO-JPEG-3] ITU-T Recommendation T.84 | ISO/IEC 10918-3:1996, + Information technology - Digital compression and + coding of continuous-tone still images: Extensions. + + [ISO-JPEG-4] ITU-T Recommendation T.86 | ISO/IEC 10918-4, + Information technology - Digital compression and + coding of continuous-tone still images: + Registration of JPEG Profiles, SPIFF Profiles, + SPIFF Tags, SPIFF colour Spaces, APPn Markers, + SPIFF, Compression types and Registration + authorities (REGAUT). + + [JFIF] JPEG File Interchange Format, Version 1.02. + Published and made freely available by C-Cube + Microsystems. Corporate Communications, 1778 + McCarthy Blvd., Milpitas, CA 95035 + + [RFC-TIFF] Parsons, G. and J. Rafferty, "Tag Image File Format + (TIFF) - image/tiff MIME Sub-type Registration", + RFC 3302, September 2002. + + [ISO-MPEG4] ISO/IEC 14496, Information technology - Coding of + Audio-Visual Objects. + + + + + + + + + + + + + + + + + + + + + + + +Singer, et al. Standards Track [Page 12] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + +7. Authors' Addresses + + David Singer + Apple Computer, Inc. + One Infinite Loop, MS:302-3MT + Cupertino CA 95014 + USA + + Phone: +1 408 974 3162 + EMail: singer@apple.com + + + Richard Clark (Current JPEG Webmaster) + Elysium Ltd + Milton House + Whitehill Road + Crowborough + East Sussex TN6 1LB + UK + + Phone: +44 1892 667411 + Fax: +44 1892 667433 + EMail: richard@elysium.ltd.uk + + + Dr. Daniel T Lee (Current JPEG Convenor) + Yahoo!, Inc. + 701, First Avenue + Sunnyvale, + California 94089, + USA + + Phone: +1 408 349 7051 + Fax: +1 253 830 0372 + EMail: dlee@yahoo-inc.com + + + + + + + + + + + + + + + + +Singer, et al. Standards Track [Page 13] + +RFC 3745 MIME Type Registrations for JPEG 2000 April 2004 + + +8. Full Copyright Statement + + Copyright (C) The Internet Society (2004). This document is subject + to the rights, licenses and restrictions contained in BCP 78 and + except as set forth therein, the authors retain all their rights. + + This document and the information contained herein are provided on an + "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE + REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE + INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR + IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF + THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED + WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. + +Intellectual Property + + The IETF takes no position regarding the validity or scope of any + Intellectual Property Rights or other rights that might be claimed + to pertain to the implementation or use of the technology + described in this document or the extent to which any license + under such rights might or might not be available; nor does it + represent that it has made any independent effort to identify any + such rights. Information on the procedures with respect to + rights in RFC documents can be found in BCP 78 and BCP 79. + + Copies of IPR disclosures made to the IETF Secretariat and any + assurances of licenses to be made available, or the result of an + attempt made to obtain a general license or permission for the use + of such proprietary rights by implementers or users of this + specification can be obtained from the IETF on-line IPR repository + at http://www.ietf.org/ipr. + + The IETF invites any interested party to bring to its attention + any copyrights, patents or patent applications, or other + proprietary rights that may cover technology that may be required + to implement this standard. Please address the information to the + IETF at ietf-ipr@ietf.org. + +Acknowledgement + + Funding for the RFC Editor function is currently provided by the + Internet Society. + + + + + + + + + +Singer, et al. Standards Track [Page 14] + |