rfc3534.txt

mediastreamer2是开源的网络传输媒体流的库

Network Working Group                                         L. Walleij
Request for Comments: 3534                      The Ogg Vorbis Community
Category: Standards Track                                       May 2003


                     The application/ogg Media Type

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 (2003).  All Rights Reserved.

Abstract

   The Ogg Bitstream Format aims at becoming a general, freely-available
   standard for transporting multimedia content across computing
   platforms and networks.  The intention of this document is to define
   the MIME media type application/ogg to refer to this kind of content
   when transported across the Internet.  It is the intention of the Ogg
   Bitstream Format developers that it be usable without intellectual
   property concerns.

Conventions used in this Document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [2].

1. The Ogg Bitstream Format

   The Ogg Bitstream format has been developed as a part of a larger
   project aimed at creating a set of components for the coding and
   decoding of multimedia content (codecs) which are to be freely
   available and freely re-implementable both in software and in
   hardware for the computing community at large, including the Internet
   community.

   Raw packets from these codecs may be used directly by transport
   mechanisms that provide their own framing and packet-separation
   mechanisms (such as UDP datagrams).




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   One such framing and content-separation mechanism is the real-time
   transport protocol (RTP).  RTP allows the streaming of synchronous
   lossy data for broadcasting and similar purposes.  If this function
   is desired then a separate RTP wrapping mechanism should be used.  A
   wrapping mechanism is currently under development.

   For stream based storage (such as files) and transport (such as TCP
   streams or pipes), Ogg codecs use the Ogg Bitstream Format to provide
   framing/sync, sync recapture after error, landmarks during seeking,
   and enough information to properly separate data back into packets at
   the original packet boundaries without relying on decoding to find
   packet boundaries.  The application/ogg MIME type refers to this kind
   of bitstreams, when no further knowledge of the bitstream content
   exists.

   The bitstream format in itself is documented in [1].

2. Registration Information

   To: [e-mail]

   Subject: Registration of MIME media type application/ogg

   MIME media type name: application

   MIME subtype name: ogg

   Required parameters: none

   Optional parameters: none

   Encoding Considerations:

   The Ogg bitstream format is binary data, and must be encoded for
   non-binary transport; the Base64 encoding is suitable for Email.
   Binary encoding could also be used.

   Security Considerations:

   As the Ogg bitstream file is a container format and only a carrier of
   content (such as Vorbis audio) with a very rigid definition (see
   [1]), this format in itself is not more vulnerable than any other
   content framing mechanism.  The main security consideration for the
   receiving application is to ensure that manipulated packages can not
   cause buffer overflows and the like.  It is possible to encapsulate
   even executable content in the bitstream, so for such uses additional
   security considerations must be taken.




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   Ogg bitstream files are not signed or encrypted using any applicable
   encryption schemes.  External security mechanisms must be added if
   content confidentiality and authenticity is to be achieved.

   Interoperability considerations:

   The Ogg bitstream format has proved to be widely implementable across
   different computing platforms.  A broadly portable reference
   implementation is available under a BSD license.

   The Ogg bitstream format is not patented and can be implemented by
   third parties without patent considerations.

   Published specification:

   See [1].

   Applications which use this media type:

   Any application that implements the specification will be able to
   encode or decode Ogg bitstream files.  Specifically, the format is
   supposed to be used by subcodecs that implement, for example, Vorbis
   audio.

   Additional information:

   Magic number(s):

   In Ogg bitstream files, the first four bytes are 0x4f 0x67 0x67 0x53
   corresponding to the string "OggS".

   File extension: .ogg

   Macintosh File Type Code(s): OggS

   Object Identifier(s) or OID(s): none

   Person & email address to contact for further information:

   Questions about this proposal should be directed to Linus Walleij
   <[e-mail]>.  Technical questions about the Ogg bitstream
   standard may be asked on the mailing lists for the developer
   community.  <http://www.xiph.org/archives/>

   Intended usage: COMMON






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   Author/Change controller:

   This document was written by Linus Walleij <[e-mail]>.
   Changes to this document will either be handled by him, a
   representative of the Xiph.org, or the associated development
   communities.

   The Ogg bitstream format is controlled by the Xiph.org and the
   respective development communities.

3. Security Considerations

   Security considerations are discussed in the security considerations
   clause of the MIME registration in section 2.

4.  Normative References

   [1]  Pfeiffer, S., "The Ogg encapsulation format version 0", RFC
        3533, May 2003.

   [2]  Bradner, S., "Key words for use in RFCs to Indicate Requirement
        Levels", BCP 14, RFC 2119, March 1997.

5.  Intellectual Property Statement

   The IETF takes no position regarding the validity or scope of any
   intellectual property 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; neither does it represent that it
   has made any effort to identify any such rights.  Information on the
   IETF's procedures with respect to rights in standards-track and
   standards-related documentation can be found in BCP-11.  Copies of
   claims of rights made available for publication 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 implementors or users of this specification can
   be obtained from the IETF Secretariat.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights which may cover technology that may be required to practice
   this standard.  Please address the information to the IETF Executive
   Director.







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6.  Author's Address

   Linus Walleij
   The Ogg Vorbis Community
   Master Olofs Vag 24
   Lund  224 66
   SE

   Phone: [phone]
   EMail: [e-mail]
   URI:   http://www.xiph.org/








































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7.  Full Copyright Statement

   Copyright (C) The Internet Society (2003).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
   and distributed, in whole or in part, without restriction of any
   kind, provided that the above copyright notice and this paragraph are
   included on all such copies and derivative works.  However, this
   document itself may not be modified in any way, such as by removing
   the copyright notice or references to the Internet Society or other
   Internet organizations, except as needed for the purpose of
   developing Internet standards in which case the procedures for
   copyrights defined in the Internet Standards process must be
   followed, or as required to translate it into languages other than
   English.

   The limited permissions granted above are perpetual and will not be
   revoked by the Internet Society or its successors or assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS 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.

Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.



















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