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Re: [Payload] Last Call: <draft-ietf-payload-rfc3189bis-02.txt> (RTP Payload Format for DV (IEC 61834) Video)) to Proposed Standard

2011-09-20 01:18:33
Hi,
I have just read this document and have some minor comments, hope it is not 
late to be taken into account.
1. Section 1:
[Qin]: It looks this version extends RFC3189 to support some new features.
However I can not see any dependency to RFC3189 in the introduction section 
until
I read the last section in this document, is it more straigtforward and clear 
to merge the section 7,8
to the introduction section and clarify how this document is different from 
RFC3189.

2. Section 3.1.1
"
3.1.1.  Media Type Registration for DV Video

   Type name:  video

   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,
         314M-25/525-60,
         314M-25/625-50,
         314M-50/525-60,
         314M-50/625-50,
         370M/1080-60i,
         370M/1080-50i,
         370M/720-60p,
         370M/720-50p,
         306M/525-60 (for backward compatibility),
         and 306M/625-50 (for backward compatibility).
"
[Qin]: In section 7, you claim you have removed SMPTE 306M, since it is covered 
by SMPTE 314M format.
However in section 3.1.2, the value for SMPTE 306M is still kept in the encode 
list. So the question is
where do you remove SMPTE 306M in this document? Why SMPTE 306M in the media 
type registration is still kept?
Does this conflict with what you said in the section 7?

The same comment applies in any place of this document where SMPTE 306M is 
still kept.

3. Section 3.1.1
"
   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 RFCXXXX
         (This document).  Other transport methods are not specified.

   Security considerations:

         See Section 4 of RFCXXXX (This document).

   Interoperability considerations:  NONE
"

 [Qin]: Is it real that there is no interoperability consideration since
Interoperability with Previous Implementations is discussed in the section 8 of 
this document?

4. Section 3.2.1
"

   Note that the examples in RFC3189 (older version of this document)
   provides incorrect SDP "a=fmtp" attribute usage.

"
[Qin]: I believe it is not appropriate to spell this note out when this 
document is published but you may put
it as errata or in the section 7.

5.  Section 3.2.1
"
   The required parameter <DV-video encoding> specifies which type of DV
   format is used.  The DV format name will be one of the following:

      SD-VCR/525-60
      SD-VCR/625-50
      HD-VCR/1125-60
      HD-VCR/1250-50
      SDL-VCR/525-60
      SDL-VCR/625-50
      314M-25/525-60
      314M-25/625-50
      314M-50/525-60
      314M-50/625-50
      370M/1080-60i
      370M/1080-50i
      370M/720-60p
      370M/720-50p
      306M/525-60 (for backward compatibility)
      306M/625-50 (for backward compatibility)
"
[Qin]: Why you need to repeat the same text in the section 3.1, why not just 
simply reference it described in the section 3.1.

6. Section 3.2.1
"
   In order to show whether the audio data is bundled into the DV stream
   or not, a format specific parameter is defined as below:
"
[Qin]: s/ a format specifc parameter/ a format of specific parameter

7. Section 3.2.1
"   The optional parameter <audio bundled> will be one of the following:
"
 [Qin] s/one of the following/one of the following value.
One question is:
How do you distinguish between required parameter or optional parameter in the 
a=fmtp line?

8. Section 3.2.2
"
3.2.2.  Usage with the SDP Offer/Answer Model

   The following considerations apply when using SDP offer-answer
   procedures [RFC3264] to negotiate the use of DV payload in RTP:

   o  The "encode" parameter can be used for sendrecv, sendonly and
      recvonly streams.  Each encode type MUST use a separate payload
      type number.

"  
[Qin]: When you are talking about encode, you are using "encoding 
type","DV-video encoding", "type of DV format" in the section 3.2,
and using "encode type" in section 3.2.2, should they be the same thing? why 
not use the same terminology for consistency?


9. Section 3.2.2
"
   In an offer for unbundled streams, in order to associate the related
   audio and video, the group attribute as defined in the Session
   Description Protocol (SDP) Grouping Framework [RFC5888] can be used.

"
[Qin]: Does it worth a exmaple to expain how SDP Grouping Framework can be used 
to correlate audio with video data in the section 3.3.1?


10. Section 3.3.1
"
   When this is done, SDP carries several m=?? lines, one for each media
   type of the session (see RFC 4566).
"
 [Qin]: What do you mean "when this is done"? It is not clear to me from the 
context.

Regards!
-Qin
----- Original Message ----- 
From: "The IESG" <iesg-secretary(_at_)ietf(_dot_)org>To: "IETF-Announce" 
<ietf-announce(_at_)ietf(_dot_)org>Cc: payload@ietf.orgSent: Monday, September 
12, 2011 12:24:16 -0700Subject: [Payload] Last Call: 
<draft-ietf-payload-rfc3189bis-02.txt> (DiameterBase Protocol) to Proposed 
StandardThe IESG has received a request from the Audio/Video Transport Payloads
WG (payload) to consider the following document:
- 'RTP Payload Format for DV (IEC 61834) Video'
  <draft-ietf-payload-rfc3189bis-02.txt> as a Proposed Standard

The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action. Please send substantive comments to the
ietf at ietf.org mailing lists by 2011-09-26. Exceptionally, comments may be
sent to iesg at ietf.org instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.

Abstract


   This document specifies the packetization scheme for encapsulating
   the compressed digital video data streams commonly known as "DV" into
   a payload format for the Real-Time Transport Protocol (RTP).  This
   document obsoletes RFC 3189.




The file can be obtained via
http://datatracker.ietf.org/doc/draft-ietf-payload-rfc3189bis/

IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-ietf-payload-rfc3189bis/


No IPR declarations have been submitted directly on this I-D.
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