MIME Type Registration for MPEG-4
draft-lim-mpeg4-mime-03

Audio-Video Transport WG Y Lim, D. Singer 
Internet Draft net&tv, Apple Computer 
Document: draft-lim-mpeg4-mime-03 October 2004 
Category: Expires March 2005 
 
 
 MIME Type Registration for MPEG-4 
 
 
Status of this Memo 
 By submitting this Internet-Draft, I certify that any applicable
 patent or other IPR claims of which I am aware have been disclosed,
 and any of which I become aware will be disclosed, in accordance with
 RFC 3668. 
 
 Internet-Drafts are working documents of the Internet Engineering 
 Task Force (IETF), its areas, and its working groups. Note that 
 other groups may also distribute working documents as 
 Internet-Drafts. 
 
 Internet-Drafts are draft documents valid for a maximum of six 
 months and may be updated, replaced, or obsoleted by other documents 
 at any time. It is inappropriate to use Internet-Drafts as 
 reference material or to cite them other than as "work in progress." 
 
 The list of current Internet-Drafts can be accessed at 
 http://www.ietf.org/1id-abstracts.txt 
 
 The list of Internet-Draft Shadow Directories can be accessed at 
 http://www.ietf.org/shadow.html 
 
 This document is a submission of the IETF AVT WG. Comments should 
 be directed to the AVT WG mailing list, avt@ietf.org. 
 
 
Abstract 
 
 This document defines the standard MIME types associated with MP4 
 files. This also document recommended use of registered MIME types 
 according to the type of contents. 
 
 
Lim and Singer July 2004 [Page 1] 
 MIME Type Registration for MPEG-4 March 2005 
 
 
 Table of Contents 
 
 1. Introduction...................................................3 
 2. Selection of MIME types for MP4 files..........................3 
 3. IANA Considerations............................................4 
 3.1 MP4 file with visual presentation..........................4 
 3.2 MP4 file without visual presentation.......................5 
 3.3 MP4 file without visual presentation.......................6 
 3.4 IOD in binary format.......................................7 
 3.5 IOD in textual format......................................8 
 4. Security Considerations........................................9 
 5. Acknowledgments................................................9 
 6. Full Copyright Statement......................................10 
 7. Intellectual Property Notice..................................10 
 8. References....................................................11 
 9. Author's Addresses............................................11 
 
 
 
 
Lim and Singer July 2004 [Page 2] 
 MIME Type Registration for MPEG-4 March 2005 
 
1. Introduction 
 
 This document describes standard definition of MIME types associated 
 with MP4 files and the guidelines for using them. 
 MPEG-4, ISO/IEC 14496, is a standard designed for the representation 
 and delivery of multimedia information over a variety of transport 
 protocols[3]. It includes interactive scene management, visual and 
 audio representations as well as systems functionality like 
 multiplexing, synchronization, and an object descriptor framework. 
 
 The historical approach for MPEG data is to declare it under "video", 
 and this approach is followed for ISO/IEC 14496. In addition some 
 MIME types are defined under "audio" and "application" for the 
 streams not containing visual presentation. 
 
 Amendment 1 of the ISO/IEC 14496 standard (also known as version 2) 
 includes a standard file type for encapsulating ISO/IEC 14496 data. 
 This file type can be used in a number of ways: perhaps the most 
 important are its use as an interchange format for ISO/IEC 14496 
 data, its use as a content-download format, and as the format read by 
 streaming media servers. 
 
 These first two uses will be greatly facilitated if there is a 
 standard MIME type for serving these files (e.g. over HTTP). 
 
 The ISO/IEC 14496 standard is broad, and therefore the type of data 
 that may be in such a file can vary. In brief, simple compressed 
 video and audio (using a number of different compression algorithms) 
 can be included; interactive scene information; meta-data about the 
 presentation; references to ISO/IEC 14496 media streams outside the 
 file and so on. Different top-level MIME types are used to identify 
 the type of the contents in the file. 
 
2. Selection of MIME types for MP4 file 
 
 The MIME types to be assigned to MP4 files are selected based on the 
 contents. Basic guidelines of selecting MIME types are as follows: 
 
 a) if the file contains neither visual nor audio presentations, but 
 only for example MPEG-J or MPEG-7, use application/mp4 
 
 b) for all other files, including those which have MPEG-J etc. in 
 addition to video or audio streams, video/mp4 should be used, 
 although: 
 
 c) for files with audio but no visual aspect, including those which 
 have MPEG-J etc. in addition to audio streams, audio/mp4 may be used. 
 
 In either case, these indicate files conforming to the "MP4" 
 specification (ISO/IEC 14496-1:2000, systems file format). 
 
Lim and Singer July 2004 [Page 3] 
 MIME Type Registration for MPEG-4 March 2005 
 
 
3. IANA Considerations 
 
 This section describes the MIME types and names to be used with 
 various MPEG-4 contents. Sections from 4.1 to 4.5 register five new 
 MIME types. 
 
3.1 MP4 file
 
 MIME media type name: video 
 
 MIME subtype name: mp4 
 
 Required parameters: none 
 
 Optional parameters: none 
 
 Encoding considerations: base64 generally preferred; files are 
 binary and should be transmitted without CR/LF conversion, 7-bit 
 stripping etc. 
 
 Security considerations: See section 5 of RFC XXXX 
 
 Interoperability considerations: A number of interoperating 
 implementations exist within the ISO/IEC 14496 community; and that 
 community has reference software for reading and writing the file 
 format. 
 
 Published specification: ISO/IEC 14496-1:2001. 
 
 Applications: Multimedia 
 
 Additional information: 
 
 Magic number(s): none 
 File extension(s): mp4 and mpg4 are both declared at 
 <http://pitch.nist.gov/nics/> 
 Macintosh File Type Code(s): mpg4 is registered with Apple 
 
 Person to contact for info: David Singer, singer@apple.com 
 
 Intended usage: Common 
 
 Author/Change controller: David Singer, ISO/IEC 14496 file format 
 chair 
Lim and Singer July 2004 [Page 4] 
 MIME Type Registration for MPEG-4 March 2005 
 
3.2 MP4 file with audio but without visual presentation 
 
 MIME media type name:audio 
 
 MIME subtype name: mp4 
 
 Required parameters: none 
 
 Optional parameters: none 
 
 Encoding considerations: base64 generally preferred; files are 
 binary and should be transmitted without CR/LF conversion, 7-bit 
 stripping etc. 
 
 Security considerations: See section 5 of RFC XXXX 
 
 Interoperability considerations: A number of interoperating 
 implementations exist within the ISO/IEC 14496 community; and that 
 community has reference software for reading and writing the file 
 format. 
 
 Published specification: ISO/IEC 14496-1:2001. 
 
 Applications: Multimedia 
 
 Additional information: 
 
 Magic number(s): none 
 File extension(s): mp4 and mpg4 are both declared at 
 <http://pitch.nist.gov/nics/> 
 Macintosh File Type Code(s): mpg4 is registered with Apple 
 
 Person to contact for info: David Singer, singer@apple.com 
 
 Intended usage: Common 
 
 Author/Change controller: David Singer, ISO/IEC 14496 file format 
 chair 
 
Lim and Singer July 2004 [Page 5] 
 MIME Type Registration for MPEG-4 March 2005 
 
3.3 MP4 file with MPEG-4 system stream and 
 neither visual nor audio presentation
 
 MIME media type name:application 
 
 MIME subtype name: mp4 
 
 Required parameters: none 
 
 Optional parameters: none 
 
 Encoding considerations: base64 generally preferred; files are 
 binary and should be transmitted without CR/LF conversion, 7-bit 
 stripping etc. 
 
 Security considerations: See section 5 of RFC XXXX 
 
 Interoperability considerations: A number of interoperating 
 implementations exist within the ISO/IEC 14496 community; and that 
 community has reference software for reading and writing the file 
 format. 
 
 Published specification: ISO/IEC 14496-1:2001. 
 
 Applications: Multimedia 
 
 Additional information: 
 
 Magic number(s): none 
 File extension(s): mp4 and mpg4 are both declared at 
 <http://pitch.nist.gov/nics/> 
 Macintosh File Type Code(s): mpg4 is registered with Apple 
 
 Person to contact for info: David Singer, singer@apple.com 
 
 Intended usage: Common 
 
 Author/Change controller: David Singer, ISO/IEC 14496 file format 
 chair 
 
Lim and Singer July 2004 [Page 6] 
 MIME Type Registration for MPEG-4 March 2005 
 
3.4 IOD in binary format 
 
 MIME media type name: application 
 
 MIME subtype name: mpeg4-iod 
 
 Required parameters: none 
 
 Optional parameters: none 
 
 Encoding considerations: base64 generally preferred; files are 
 binary and should be transmitted without CR/LF conversion, 7-bit 
 stripping etc. 
 
 Security considerations: See section 5 of RFC XXXX 
 
 Interoperability considerations: A number of interoperating 
 implementations exist within the ISO/IEC 14496 community; and that 
 community has reference software for reading and writing the file 
 format. 
 
 Published specification: ISO/IEC 14496-1:2001 
 
 Applications: Multimedia 
 
 Additional information: 
 
 Magic number(s): none 
 File extension(s): none mp4 and mpg4 are both declared at 
 <http://pitch.nist.gov/nics/> 
 Macintosh File Type Code(s): mpg4 is registered with Apple 
 
 Person to contact for info: David Singer, singer@apple.com 
 
 Intended usage: Common 
 
 Author/Change controller: David Singer, ISO/IEC 14496 file format 
 chair 
 
Lim and Singer July 2004 [Page 7] 
 MIME Type Registration for MPEG-4 March 2005 
 
3.5 IOD in textual format 
 
 MIME media type name: application 
 
 MIME subtype name: mpeg4-iod-xmt 
 
 Required parameters: none 
 
 Optional parameters: none 
 
 Encoding considerations: none 
 
 Security considerations: See section 5 of RFC XXXX 
 
 Interoperability considerations: A number of interoperating 
 implementations exist within the ISO/IEC 14496 community; and that 
 community has reference software for reading and writing the file 
 format. 
 
 Published specification: ISO/IEC 14496-1:2001 AMD2. 
 
 Applications: Multimedia 
 
 Additional information: 
 
 Magic number(s): none 
 File extension(s): mp4 and mpg4 are both declared at 
 <http://pitch.nist.gov/nics/> 
 Macintosh File Type Code(s): mpg4 is registered with Apple 
 
 Person to contact for info: David Singer, singer@apple.com 
 
 Intended usage: Common 
 
 Author/Change controller: David Singer, ISO/IEC 14496 file format 
 chair 
 
Lim and Singer July 2004 [Page 8] 
 MIME Type Registration for MPEG-4 March 2005 
 
 
 
4. Security Considerations 
 
 It is possible to inject non-compliant MPEG streams (Audio, Video, 
 and Systems) in the MP4 file to overload the receiver/decoder's 
 buffers which might compromise the functionality of the receiver 
 or even crash it. This is especially true for end-to-end systems 
 like MPEG where the buffer models are precisely defined. 
 
 MP4 file supports storage of stream types including commands that 
 are executed on the terminal like OD commands, BIFS commands, etc. 
 and programmatic content like MPEG-J (Java(TM) Byte Code) and 
 ECMASCRIPT. It is possible to use one or more of the above in a 
 manner non-compliant to MPEG to crash or temporarily make the 
 receiver unavailable. 
 
 Authentication mechanisms can be used to validate of the sender and 
 the data to prevent security problems due to non-compliant malignant 
 MP4 file.
 
 A security model is defined in ISO/IEC 14496 Systems MP4 files 
 containing MPEG-J contents which comprises Java(TM) classes and 
 objects. MPEG-J defines a set of Java APIs and a secure execution 
 model. MPEG-J content can call this set of APIs and Java(TM) methods 
 from a set of Java packages supported in the receiver within the 
 defined security model. According to this security model, downloaded 
 byte code is forbidden to load libraries, define native methods, 
 start programs, read or write files, or read system properties. 
 
 
5. Acknowledgments 
 
 This draft has benefited greatly by contributions from many people, 
 including Mike Coleman, Jean-Claude Duford, Viswanathan Swaminathan, 
 Peter Westerink, Carsten Herpel, Olivier Avaro, Paul Christ, Zvi 
 Lifshitz, and many others. Their insight, foresight, and 
 contribution is gratefully acknowledged. Little has been invented 
 here by the author; this is mostly a collation of greatness that has 
 gone before. 
Lim and Singer July 2004 [Page 9] 
 MIME Type Registration for MPEG-4 March 2005 
 
 
 
6. 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. 
 
 
7. Intellectual Property Notice 
 
 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. 
 
 
 
Lim and Singer July 2004 [Page 10] 
 MIME Type Registration for MPEG-4 March 2005 
 
8. References 
8.1 Normative References
 
 [1]Bradner, S., "The Internet Standards Process -- Revision 3", BCP 
 9, RFC 2026, October 1996. 
 
 [2]Bradner, S., "Key words for use in RFCs to Indicate Requirement 
 Levels", BCP 14, RFC 2119, March 1997 
 
 [3]H. Schulzrinne, et. al., "RTP : A Transport Protocol for Real-Time 
 Applications", IETF RFC 1889, January 1996. 
 
 [4]ISO/IEC 14496-1 "Information technology - Coding of audio-visual 
 objects - Part 1 : Systems", 3rd ed. 2004 
 
 [5]ISO/IEC 14496-12 "Information technology - Coding of audio-visual 
 objects - Part 12 : ISO Base Media File Format", December 2003 
 
 [6]ISO/IEC 14496-14 "Information technology - Coding of audio-visual 
 objects - Part 14 : MP4 File Format", January 2004 
 
 [7]ISO/IEC 14496-15 "Information technology - Coding of audio-visual 
 objects - Part 15 : AVC File Format", 2004 
 
9. Author's Addresses 
 
 
 Young-Kwon LIM 
 net&tv Inc. 
 Room 802 Hanseo Building 
 1582-6 Seocho-3-Dong Seocho-Gu
 Seoul, 137-875, Korea 
 E-mail : young@netntv.co.kr 
 TEL : +82-2-581-2305 
 
 
 David Singer 
 Apple Computer, Inc. 
 One Infinite Loop, MS:302-3MT 
 Cupertino CA 95014 
 USA 
 Email: singer@apple.com 
 Tel: +1 408 974 3162 
 
 
 
Lim and Singer July 2004 [Page 11]