rfc3189.txt

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   This describes a session where audio and video streams are sent
   separately.  The session is sent to a multicast group 224.2.17.12.
   The audio is sent using L16 format, and the video is sent using SD-
   VCR 525/60 format which corresponds to NTSC format in consumer DV.

3.2 SDP description for bundled streams

   When sending a bundled stream, all the DIF blocks including system
   data will be sent through a single RTP stream.  An example SDP
   description for a bundled DV stream is:

















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RFC 3189      RTP Payload Format for DV (IEC 61834) Video   January 2002


      v=0
      o=ikob 2890844526 2890842807 IN IP4 126.16.64.4
      s=POI Seminar
      i=A Seminar on how to make Presentations on the Internet
      u=http://www.koganei.wide.ad.jp/~ikob/POI/index.html
      e=[e-mail] (Katsushi Kobayashi)
      c=IN IP4 224.2.17.12/127
      t=2873397496 2873404696
      m=video 49170 RTP/AVP 112 113
      a=rtpmap:112 DV/90000
      a=fmtp: 112 encode=SD-VCR/525-60
      a=fmtp: 112 audio=bundled
      a=fmtp: 113 encode=306M/525-60
      a=fmtp: 113 audio=bundled

   This SDP record describes a session where audio and video streams are
   sent bundled.  The session is sent to a multicast group 224.2.17.12.
   The video is sent using both 525/60 consumer DV and SMPTE standard
   306M formats, when the payload type is 112 and 113, respectively.

4. Security Considerations

   RTP packets using the payload format defined in this specification
   are subject to the security considerations discussed in the RTP
   specification [6], and any appropriate RTP profile.  This implies
   that confidentiality of the media streams is achieved by encryption.
   Because the data compression used with this payload format is applied
   to end-to-end, encryption may be performed after compression so there
   is no conflict between the two operations.

   A potential denial-of-service threat exists for data encodings using
   compression techniques that have non-uniform receiver-end
   computational load.  The attacker can inject pathological datagrams
   into the stream which are complex to decode and cause the receiver to
   be overloaded.  However, this encoding does not exhibit any
   significant non-uniformity.

   As with any IP-based protocol, in some circumstances a receiver may
   be overloaded simply by the receipt of too many packets, either
   desired or undesired.  Network-layer authentication may be used to
   discard packets from undesired sources, but the processing cost of
   the authentication itself may be too high.  In a multicast
   environment, pruning of specific sources may be implemented in future
   versions of IGMP [14] and in multicast routing protocols to allow a
   receiver to select which sources are allowed to reach it.






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RFC 3189      RTP Payload Format for DV (IEC 61834) Video   January 2002


5. IANA Considerations

   This document defines a new RTP payload name and associated MIME
   type, DV.  The registration forms for the MIME types for both video
   and audio are shown in the next sections.

5.1 DV video MIME registration form

   MIME media type name: video

   MIME subtype name: DV

   Required parameters:
      encode: type of DV format.  Permissible values for encode are
         SD-VCR/525-60, SD-VCR/625-50, HD-VCR/1125-60 HD-VCR/1250-50,
         SDL-VCR/525-60, SDL-VCR/625-50, 306M/525-60, 306M/625-50,
         314M-25/525-60, 314M-25/625-50, 314M-50/525-60, and
         314M-50/625-50.

   Optional parameters:
      audio: whether the DV stream includes audio data or not.
         Permissible values for audio are bundled and none.  Defaults to
         none.

   Encoding considerations:
      DV video can be transmitted with RTP as specified in RFC 3189.
      Other transport methods are not specified.

   Security considerations:
      See Section 4 of RFC 3189.

   Interoperability considerations: NONE

   Published specification: IEC 61834 Standard
      SMPTE 306M
      SMPTE 314M
      RFC 3189

   Applications which use this media type:
      Video communication.

   Additional information: None
      Magic number(s): None
      File extension(s): None
      Macintosh File Type Code(s): None






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RFC 3189      RTP Payload Format for DV (IEC 61834) Video   January 2002


   Person & email address to contact for further information:
      Katsushi Kobayashi
      e-mail: [e-mail]

   Intended usage: COMMON

   Author/Change controller:
      Katsushi Kobayashi
      e-mail: [e-mail]

5.2 DV audio MIME registration form

   MIME media type name: audio

   MIME subtype name: DV

   Required parameters:
      encode: type of DV format.  Permissible values for encode are
         SD-VCR/525-60, SD-VCR/625-50, HD-VCR/1125-60 HD-VCR/1250-50,
         SDL-VCR/525-60, SDL-VCR/625-50, 306M/525-60, 306M/625-50,
         314M-25/525-60, 314M-25/625-50, 314M-50/525-60, and
         314M-50/625-50.

   Optional parameters: NONE

   Encoding considerations:
      DV audio can be transmitted with RTP as specified in RFC 3189.
      Other transport methods are not specified.

   Security considerations:
      See Section 4 of RFC 3189.

   Interoperability considerations: NONE

   Published specification: IEC 61834 Standard
      SMPTE 306M
      SMPTE 314M
      RFC 3189

   Applications which use this media type:
      Audio communication.

   Additional information: None
      Magic number(s): None
      File extension(s): None
      Macintosh File Type Code(s): None





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RFC 3189      RTP Payload Format for DV (IEC 61834) Video   January 2002


   Person & email address to contact for further information:
      Katsushi Kobayashi
      e-mail: [e-mail]

   Intended usage: COMMON

   Author/Change controller:
      Katsushi Kobayashi
      e-mail: [e-mail]

6. References

   [1]   IEC 61834, Helical-scan digital video cassette recording system
         using 6,35 mm magnetic tape for consumer use (525-60, 625-50,
         1125-60 and 1250-50 systems).

   [2]   IEC 61883, Consumer audio/video equipment - Digital interface.

   [3]   IEEE Std 1394-1995, Standard for a High Performance Serial Bus

   [4]   SMPTE 306M, 6.35-mm type D-7 component format - video
         compression at 25Mb/s -525/60 and 625/50.

   [5]   SMPTE 314M, Data structure for DV-based audio and compressed
         video 25 and 50Mb/s.

   [6]   Schulzrinne, H., Casner, S., Frederick, R. and V. Jacobson,
         "RTP: A transport protocol for real-time applications", RFC
         1889, January 1996.

   [7]   Hoffman, D., Fernando, G., Goyal, V. and M. Civanlar, "RTP
         Payload Format for MPEG1/MPEG2 Video", RFC 2250, January 1998.

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

   [9]   ISO/IEC 11172, Coding of moving pictures and associated audio
         for digital storage media up to about 1,5 Mbits/s.

   [10]  ISO/IEC 13818, Generic coding of moving pictures and associated
         audio information.

   [11]  Schulzrinne, H., "RTP Profile for Audio and Video Conferences
         with Minimal Control", RFC 1890, January 1996.

   [12]  Kobayashi, K., Ogawa, A., Casner S. and C. Bormann, "RTP
         Payload Format for 12-bit DAT Audio and 20- and 24-bit Linear
         Sampled Audio", RFC 3190, January 2002.



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RFC 3189      RTP Payload Format for DV (IEC 61834) Video   January 2002


   [13]  Handley, M. and V. Jacobson, "SDP: Session Description
         Protocol", RFC 2327, April 1998.

   [14]  Deering, S., "Host Extensions for IP Multicasting", STD 5, RFC
         1112, August 1989.

7. Authors' Addresses

   Katsushi Kobayashi
   Communication Research Laboratory
   4-2-1 Nukii-kitamachi,
   Koganei Tokyo 184-8795 JAPAN

   EMail: [e-mail]


   Akimichi Ogawa
   Keio University
   5322 Endo,
   Fujisawa Kanagawa 252 JAPAN

   EMail: [e-mail]


   Stephen L. Casner
   Packet Design
   2465 Latham Street
   Mountain View, CA 94040 United States

   EMail: [e-mail]


   Carsten Bormann
   Universitaet Bremen TZI
   Postfach 330440
   D-28334 Bremen, Germany

   Phone: [phone]
   Fax:   [phone]
   EMail: [e-mail]: [e-mail]











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RFC 3189      RTP Payload Format for DV (IEC 61834) Video   January 2002


8.  Full Copyright Statement

   Copyright (C) The Internet Society (2002).  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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