Subject: [AVT] MPEG2-TS preamble in draft-begen-avt-rtp-mpeg2ts-preamble-03

From: Roni Even <[email-masked]>
Date: Wed, 02 Dec 2009 10:14:34 +0200

Hi,

I reviewed the draft and have some questions.

I am not sure what is the purpose of section 4 titled "elements of delay in
video systems", in my view the only relevant information in section 4 to
this draft are sections 4.1 and 4.2.1. The rest of the information is
general and can be part of the base RAMS draft and may be helpful when
designing solutions for reducing end to end delay.

What I find missing in the draft is the information about what  part of the
PSI information should be sent (or MUST be sent) by the RS in the preamble
stream, do you leave it open for implementation?

One comment - In section 4.1 second paragraph you list the elements of the
PSI data, is this the whole list, maybe you should reference table 2-28 in
H.222.0.

Thanks

Roni Even as individual

---

From: "Ali C. Begen (abegen)" <[email-masked]>
Date: Wed, 2 Dec 2009 07:06:16 -0800

Hi Roni,

See inline.

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]] On Behalf Of Roni Even
> Sent: Wednesday, December 02, 2009 3:15 AM
> To: [email-masked]
> Subject: [AVT] MPEG2-TS preamble in draft-begen-avt-rtp-mpeg2ts-preamble-03
> 
> Hi,
> 

Thanks.

> I am not sure what is the purpose of section 4 titled "elements of delay in video
> systems", in my view the only relevant information in section 4 to this draft are sections
> 4.1 and 4.2.1. The rest of the information is general and can be part of the base RAMS
> draft and may be helpful when designing solutions for reducing end to end delay.

The sections 4.2.2 and 4.3 are also related to video (although not that specific to MPEG2-TS but they apply to MPEG2-TS as well). But, if my memory serves well, we decided to move all of the video discussion from the RAMS draft early in the process.
 
> 
> What I find missing in the draft is the information about what  part of the PSI
> information should be sent (or MUST be sent) by the RS in the preamble stream, do you
> leave it open for implementation?

Good question. We listed all the possibilities and register their TLOV types. We provide some guidelines, too. But, your intuition is correct. Whatever needs to be sent is usually implementation specific.
 
> One comment - In section 4.1 second paragraph you list the elements of the PSI data, is
> this the whole list, maybe you should reference table 2-28 in H.222.0.

It is more or less a general definition for PSI. We can add this reference there to make it more clear, though.

Cheers, acbegen.

---

From: "Bill Ver Steeg (versteb)" <[email-masked]>
Date: Wed, 2 Dec 2009 10:10:53 -0500

Regarding section 4-

We intentionally removed all references to video flows from the RAMS
draft, and made a note to move the media-specific components of delay
/acceleration to the media specific drafts. I think we came pretty close
to making this happen, but I can help wordsmith if we missed the mark.

Bill VerSteeg 

From: [email-masked] [mailto:[email-masked]] On Behalf Of
Roni Even
Sent: Wednesday, December 02, 2009 3:15 AM
To: [email-masked]
Subject: [AVT] MPEG2-TS preamble in
draft-begen-avt-rtp-mpeg2ts-preamble-03

Hi,

I am not sure what is the purpose of section 4 titled "elements of delay
in video systems", in my view the only relevant information in section 4
to this draft are sections 4.1 and 4.2.1. The rest of the information is
general and can be part of the base RAMS draft and may be helpful when
designing solutions for reducing end to end delay.

What I find missing in the draft is the information about what  part of
the PSI information should be sent (or MUST be sent) by the RS in the
preamble stream, do you leave it open for implementation?

One comment - In section 4.1 second paragraph you list the elements of
the PSI data, is this the whole list, maybe you should reference table
2-28 in H.222.0.

Thanks

Roni Even as individual

---

From: Roni Even <[email-masked]>
Date: Wed, 02 Dec 2009 18:42:19 +0200

Hi,

I just made the observation that there are parts of section 4 that are not
related to the preamble draft. 

As for RAMS I am not sure what was the conclusion, I thought it was about
removing the MPEG2 specific text and not general text.

Roni Even as Individual

From: Bill Ver Steeg (versteb) [mailto:[email-masked]] 
Sent: Wednesday, December 02, 2009 5:11 PM
To: Roni Even; [email-masked]
Subject: RE: [AVT] MPEG2-TS preamble in
draft-begen-avt-rtp-mpeg2ts-preamble-03

Regarding section 4-

We intentionally removed all references to video flows from the RAMS draft,
and made a note to move the media-specific components of delay /acceleration
to the media specific drafts. I think we came pretty close to making this
happen, but I can help wordsmith if we missed the mark.

Bill VerSteeg 

From: [email-masked] [mailto:[email-masked]] On Behalf Of Roni
Even
Sent: Wednesday, December 02, 2009 3:15 AM
To: [email-masked]
Subject: [AVT] MPEG2-TS preamble in draft-begen-avt-rtp-mpeg2ts-preamble-03

Hi,

Thanks

Roni Even as individual