Re: ISSUE-330 (Is Presented Region a synonym for temporally active region?): Is Presented Region a synonym for temporally active region? [TTML IMSC 1.0]

Apologies this should have been on ISSUE-310 - I’ve added it there also.

Nigel


On 13/08/2014 10:35, "Nigel Megitt" <nigel.megitt@bbc.co.uk> wrote:

>Hi Pierre,
>
>I¹ve added a note to ISSUE-330, quoted here for convenience:
>
>The updated text uses phrases such as Œearlier/later in the document¹ -
>this does not address my original concern, that the test for earlier and
>later is not precisely enough defined. Do you mean to compare the byte
>locations of the opening tag of the elements in the flattened document
>structure, for example?
>
>It is also unclear in the new wording (list item 2) how an ISD ³maps² to a
>content element. An ISD is typically constructed from multiple elements
>simultaneously. There seems to be an assumption that an ISD can only
>relate to a single p, which is such a significant constraint that I wonder
>if it was intended.
>
>Take this example:
>
><p id="p1" begin="00:01:00" end="00:02:00">
>[some stuff]
></p>
><p id="p2" begin="00:01:30" end="00:01:45">
>[some other stuff]
></p>
>
>We have here the following ISDs:
>1. 00:01:00 containing p1
>2. 00:01:30 containing p1 and p2
>3. 00:01.45 containing p1
>4. 00:02:00 containing nothing
>
>Is this progressively decodable? Did the 3rd ISD above 'map' to p2? It
>doesn't itself contain p2: it simply has its timing derived from p2.
>
>
>Kind regards,
>
>
>Nigel
>
>
>
>On 12/08/2014 15:51, "Pierre-Anthony Lemieux" <pal@sandflow.com> wrote:
>
>>Addressed at https://dvcs.w3.org/hg/ttml/rev/ceaa219bfbcc .
>>
>>Best,
>>
>>-- Pierre
>>
>>On Mon, Jul 28, 2014 at 5:55 PM, Nigel Megitt <nigel.megitt@bbc.co.uk>
>>wrote:
>>> Thanks for the clarification Glenn. I've added a note to ISSUE-330
>>>which
>>> I'll quote to save clicks:
>>>
>>> "In that case it would make sense to define 'presented region' in terms
>>>of a
>>> 'temporally active region' that either contains visible content with
>>>opacity
>>>>0 or has showBackground="always" and a backgroundColour with opacity
>>>>>0."
>>>
>>> Nigel
>>>
>>>
>>> On 28/07/2014 16:41, "Glenn Adams" <glenn@skynav.com> wrote:
>>>
>>> No, temporally active region and presented region are not synonymous.
>>> Further, showBackground="whenActive" does not mean "when temporally
>>>active",
>>> rather it means "when temporally active and has content selected into
>>>it".
>>> As such it is a bit of a misnomer, but we adopted the name from SMIL
>>>and
>>> repurposed it to our ends.
>>>
>>> See my additional comments in Issues 314 and 330.
>>>
>>>
>>> On Mon, Jul 28, 2014 at 6:56 AM, Timed Text Working Group Issue Tracker
>>> <sysbot+tracker@w3.org> wrote:
>>>>
>>>> ISSUE-330 (Is Presented Region a synonym for temporally active
>>>>region?):
>>>> Is Presented Region a synonym for temporally active region? [TTML IMSC
>>>>1.0]
>>>>
>>>> http://www.w3.org/AudioVideo/TT/tracker/issues/330

>>>>
>>>> Raised by: Nigel Megitt
>>>> On product: TTML IMSC 1.0
>>>>
>>>> This issue is related to Issue-314 and was generated as part of the
>>>> resolution to Issue-313.
>>>>
>>>> TTML 1 SE §9.3.2 [1] uses the term "temporally active region" to
>>>>define
>>>> regions that are included in the construction of intermediate
>>>>synchronic
>>>> documents "for the purposes of performing presentation processing".
>>>> Issue-314 covers the point that this term is not defined.
>>>>
>>>> [1] http://www.w3.org/TR/ttml1/#semantics-region-layout-step-1

>>>>
>>>> IMSC 1 editor's draft §4.6.1 [2] defines and uses the term "presented
>>>> region" to define regions that may be presented at any moment, and in
>>>>all
>>>> but one case references presented region with respect to an
>>>>intermediate
>>>> synchronic document.
>>>>
>>>> [2]
>>>> 
>>>>https://dvcs.w3.org/hg/ttml/raw-file/tip/ttml-ww-profiles/ttml-ww-profi

>>>>l
>>>>es.html#presented-region
>>>>
>>>> It looks as though these two terms may be synonyms, or very closely
>>>> related to each other. If this is the case then IMSC 1 should
>>>>reference the
>>>> defined term in TTML 1 SE (if need be, after the resolution to
>>>>Issue-314).
>>>> If it is not the case then the difference should be clarified making
>>>> reference to the similar concept.
>>>>
>>>> For example, if the resolution to Issue-314 is to define temporally
>>>>active
>>>> region in TTML 1 SE as any region that is either temporally active or
>>>>has
>>>> content selected into it that is temporally active, or has
>>>> showBackground="always", then Presented Region in IMSC 1 may be
>>>>defined as:
>>>>    any temporally active region which satisfies all of the following
>>>> conditions...,
>>>>    where those conditions include [those currently specified] and
>>>>those
>>>> noted additionally by Glenn in response to Issue-313 [3], i.e. the
>>>>values of
>>>> the attributes tts:display, tts:visibility, tts:extent and tts:opacity
>>>>are
>>>> such that marks may be made by the region or its contents.
>>>>
>>>> [3] http://lists.w3.org/Archives/Public/public-tt/2014Jul/0036.html

>>>>
>>>> This issue created as per Action-308.
>>>>
>>>>
>>>>
>>>
>
>

Received on Wednesday, 13 August 2014 09:38:35 UTC