Subject: [AVTCORE] I-D Action: draft-ietf-payload-rtp-ttml-06.txt

From: [email-masked]
Date: Tue, 19 Nov 2019 08:31:31 -0800

A New Internet-Draft is available from the on-line Internet-Drafts directories.
This draft is a work item of the Audio/Video Transport Core Maintenance WG of the IETF.

        Title           : RTP Payload for TTML Timed Text
        Author          : James Sandford
	Filename        : draft-ietf-payload-rtp-ttml-06.txt
	Pages           : 17
	Date            : 2019-11-19

Abstract:
   This memo describes a Real-time Transport Protocol (RTP) payload
   format for TTML, an XML based timed text format for live and file
   based workflows from W3C.  This payload format is specifically
   targeted at live workflows using TTML.

The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-ietf-payload-rtp-ttml/

There are also htmlized versions available at:
https://tools.ietf.org/html/draft-ietf-payload-rtp-ttml-06
https://datatracker.ietf.org/doc/html/draft-ietf-payload-rtp-ttml-06

A diff from the previous version is available at:
https://www.ietf.org/rfcdiff?url2=draft-ietf-payload-rtp-ttml-06

Please note that it may take a couple of minutes from the time of submission
until the htmlized version and diff are available at tools.ietf.org.

Internet-Drafts are also available by anonymous FTP at:
ftp://ftp.ietf.org/internet-drafts/

---

From: Martin J. Dürst <[email-masked]>
Date: Fri, 22 Nov 2019 07:02:17 +0000

Sorry that this only just now cought my eye, but the document is in the 
RFC Editor's queue for only 1 day yet, and I think there are serious 
editorial changes that would improve the document quite a bit.

The document mentions the word "workflow" to describe TTML several 
times, in particular two times in the abstract. This was surprising to 
me because while I have been involved in W3C for a long time, I have 
never heard the word "workflow" in connection with TTTML.

I just checked, and indeed Timed Text Markup Language 2 (TTML2)
(W3C Recommendation 08 November 2018, https://www.w3.org/TR/ttml2/) 
doesn't mention the word "workflow" a single time. The way TTML 
describes itself is:

    The Timed Text Markup Language is a content type that
    represents timed text media for the purpose of interchange
    among authoring systems. Timed text is textual information
    that is intrinsically or extrinsically associated with
    timing information.

The word "workflow" may have a very specific meaning in the television 
industry, which lead the author of this document to choose this word, 
but it is very confusing for readers not familiar with such terminology. 
So in order to avoid such confusion, I strongly suggest to 
remove/replace the word "workflow" from the document, and in particular 
from the abstract. Given the nature of RTP, it seems to me that it's 
pretty obvious that a payload format is needed for 'live' use cases, and 
not for file transfer (which may be done with HTTP or FTP or whatever 
else). So I don't think there is a need to bring in the specific 
viewpoint of the TV industry and therewith confuse people from other 
industries and describe TTML in a completely different way than people 
in general are understanding it.

Sorry this got a bit long, but I hope I got my point across. If I should 
send this somewhere else, please tell me.

Regards,   Martin.

-------- Forwarded Message --------
Subject: I-D Action: draft-ietf-payload-rtp-ttml-06.txt
Date: Tue, 19 Nov 2019 08:31:31 -0800
From: [email-masked]
Reply-To: [email-masked], [email-masked]
To: [email-masked]
CC: [email-masked]

A New Internet-Draft is available from the on-line Internet-Drafts 
directories.
This draft is a work item of the Audio/Video Transport Core Maintenance 
WG of the IETF.

Abstract:

_______________________________________________
I-D-Announce mailing list
[email-masked]
https://www.ietf.org/mailman/listinfo/i-d-announce
Internet-Draft directories: http://www.ietf.org/shadow.html
or ftp://ftp.ietf.org/ietf/1shadow-sites.txt
.

---

From: James Sandford <[email-masked]>
Date: Fri, 22 Nov 2019 07:56:36 +0000

Hello,
Thanks for your comments. I don't believe "workflow" is broadcast specific. I've seen it used in the context of many processes where multiple actors handle something in sequence. This includes manufacturing workflows, software development workflows, and even RFC creation. From the tools.ietf.org page:

    The New Internet Draft Submission Tool replaces the older Draft Submission Tool and the even older email submission workflow

Are you unfamiliar with the term "workflow" or suggesting its inappropriate in this context?

Regards,
James

==========
James Sandford
R&D Project Engineer

BBC Research and Development
5th Floor
Dock House
MediaCityUK
Salford
M50 2LH

Tel: 030304 (09549)
Web: http://www.bbc.co.uk/rd

________________________________________
From: Martin J. Dürst [[email-masked]]
Sent: 22 November 2019 07:02
To: Barry Leiba; Roni Even; James Sandford
Cc: [email-masked]
Subject: Fwd: I-D Action: draft-ietf-payload-rtp-ttml-06.txt

Regards,   Martin.

-------- Forwarded Message --------
Subject: I-D Action: draft-ietf-payload-rtp-ttml-06.txt
Date: Tue, 19 Nov 2019 08:31:31 -0800
From: [email-masked]
Reply-To: [email-masked], [email-masked]
To: [email-masked]
CC: [email-masked]

Abstract:

---

From: Barry Leiba <[email-masked]>
Date: Fri, 22 Nov 2019 16:03:10 +0800

> Are you unfamiliar with the term "workflow" or suggesting its inappropriate in this context?

The latter, James.

Barry

---

From: Martin J. Dürst <[email-masked]>
Date: Fri, 22 Nov 2019 08:57:47 +0000

Hello James,

Many thanks for your fast reply.

> Are you unfamiliar with the term "workflow" or suggesting its inappropriate in this context?

The later, not the former. (In the context of your other examples above, 
the word workflow seems very natural to me.)

Regards,   Martin.

---

From: James Sandford <[email-masked]>
Date: Fri, 22 Nov 2019 10:01:42 +0000

Could you expand? Workflow feels like the correct term for the context of moving the media between endpoints in a generic sense to me.

Regards,
James

==========
James Sandford
R&D Project Engineer

Tel: 030304 (09549)

________________________________________
From: Martin J. Dürst [[email-masked]]
Sent: 22 November 2019 08:57
To: James Sandford; Barry Leiba; Roni Even
Cc: [email-masked]
Subject: Re: I-D Action: draft-ietf-payload-rtp-ttml-06.txt

Hello James,

Regards,   Martin.

---

From: Martin J. Dürst <[email-masked]>
Date: Fri, 22 Nov 2019 10:55:26 +0000

Hello James,

> Could you expand? Workflow feels like the correct term for the context of moving the media between endpoints in a generic sense to me.

What doesn't work for me is that the first sentence in the Abstract says 
"TTML, an XML based timed text format for live and file based workflows 
from W3C". What does TTML *itself* have to do with workflows, other than 
that any kind of data format whatever can be integrated into dozens if 
not hundreds of different workflows?

Looking at the document a bit more, I also found one instance where 
"Television Workflows" is capitalized, which surprises me, but may 
indicate that "workflow" has a somewhat specific use in the TV industry.

Also, in the last instance of "workflow" in the document, it is 
"streaming workflows" rather than "live workflows". To me, "streaming" 
sounds like the better word (for the second sentence of the abstract), 
because it's less specific to TV, and my understanding (as an outsider) 
would be that this RTP Payload is not restricted to live broadcasts, but 
can also be used for streaming pre-recorded programming.

Hope this helps.

Regards,   Martin.

---

From: James Sandford <[email-masked]>
Date: Fri, 22 Nov 2019 11:04:12 +0000

Thank you. This helps a lot. 

The capitalisation is a mistake. Thanks for spotting.

I think I agree with your points on the first sentence of the abstract and I understand your point on the use of "live workflows". 

Proposed changes:

    Remove the workflows section of the first sentence in the abstract. Updated wording:
        This memo describes a Real-time Transport Protocol (RTP) payload format for TTML, an XML based timed text format from W3C.

    Replace instances of "live workflows" with "streaming workflows".

    Fix capitalisation mentioned. 

Would that be acceptable? 

Regards,
James

==========
James Sandford
R&D Project Engineer

Tel: 030304 (09549)

Sent: 22 November 2019 10:55

Hello James,

Hope this helps.

Regards,   Martin.

---

From: Martin J. Dürst <[email-masked]>
Date: Sat, 23 Nov 2019 00:43:20 +0000

Hello James,

Many thank again for your quick followup.

> Would that be acceptable?

That would be great.

Regards,   Martin.

---

From: Barry Leiba <[email-masked]>
Date: Sat, 23 Nov 2019 08:52:22 +0800

Nice; thanks for the review, Martin.

James, please keep this in your notes and we can handle it during AUTH48.

Barry

---

From: James Sandford <[email-masked]>
Date: Mon, 25 Nov 2019 10:01:23 +0000

Shall do. Thanks Martin & Barry.

Regards,
James.

==========
James Sandford
R&D Project Engineer

Tel: 030304 (09549)

________________________________________
From: Barry Leiba [[email-masked]]
Sent: 23 November 2019 00:52
To: Martin J. Dürst
Cc: James Sandford; Roni Even; [email-masked]
Subject: Re: I-D Action: draft-ietf-payload-rtp-ttml-06.txt

Barry