Re: ISSUE-261: signaling docoument profile conformance is separate from decoder presentation requirements [TTML.next]

>  I still maintain
> that the profile must be definable in prose or other means without actually
> creating and/or posting a resolvable profile document that conforms to the
> feature syntax defined in TTML.

Yes. I had interpreted "a URI which is feasibly resolvable to a
definition of a content profile" as meaning "not necessarily
resolvable" :)

On Fri, Jul 12, 2013 at 1:40 PM, Michael Dolan <mdolan@newtbt.com> wrote:
> Agreed.  But the inline form is already permitted, and I don't see a
> compelling reason to disallow it. That said, I would expect the "normal"
> case is to use a URI.
>
> Since you said "URI" and not URL, it begs that we return to the question of
> resolvability and existence of the TTML syntax profile.  I still maintain
> that the profile must be definable in prose or other means without actually
> creating and/or posting a resolvable profile document that conforms to the
> feature syntax defined in TTML. The feature granularity is insufficient to
> describe any (I think) of the profiles in use today. Minimally there are
> certainly profile examples that cannot be (sdp-us and cff-tt). The feature
> mechanism cannot be extended by 3rd parties. This effectively forces
> permitting the profiles to be defined by other means, and therefore, there
> cannot necessarily be a profile document, and therefore cannot be resolvable
> in all cases.
>
> Regards,
>
>         Mike
>
> -----Original Message-----
> From: Pierre-Anthony Lemieux [mailto:pal@sandflow.com]
> Sent: Friday, July 12, 2013 1:24 PM
> To: Glenn Adams
> Cc: Timed Text Working Group
> Subject: Re: ISSUE-261: signaling docoument profile conformance is separate
> from decoder presentation requirements [TTML.next]
>
>> Is there a use case for having a document include inline the definition of
> a content profile it claims to conform to?
>
> Such a use case does not immediately come to (my) mind.
>
> -- Pierre
>
> On Fri, Jul 12, 2013 at 1:18 PM, Glenn Adams <glenn@skynav.com> wrote:
>> Is there a use case for having a document include inline the
>> definition of a content profile it claims to conform to? Or is it
>> sufficient to allow a document to refer to a URI which is feasibly
>> resolvable to a definition of a content profile?
>>
>>
>> On Fri, Jul 12, 2013 at 2:08 PM, Pierre-Anthony Lemieux
>> <pal@sandflow.com>
>> wrote:
>>>
>>> > > Some means must be defined to separately signal these different
>>> > > semantics.
>>> > For example, we could create a new element and attribute -
>>> > <ContentProfile> and contentProfile.
>>>
>>> Sounds good. I also see value in exploring means for (a) defining a
>>> content profile and (b) signaling conformance of a document to one or
>>> more content profile.
>>>
>>> > <ContentProfile>
>>>
>>> What about following the <ttp:profile> template with the following
> tweaks:
>>>
>>> - adding a @designator attribute allowing the content profile
>>> designator to be specified
>>> - @use can contain one or more URIs, each identifying a content
>>> profile to be included in its entirety by reference, thereby avoiding
>>> having to repeat all features already defined in another profile.
>>> Perhaps @use can reference "profile" even when defining
>>> "contentProfile" so that existing content designator can be used.
>>> - allowing constraints over a base content profile to be specified
>>> using value="prohibited"
>>>
>>> <contentprofile designator="http://example.noname/profile1"
>>> use="http://example.noname/profile4 http://example.noname/profile3"
>>> xmlns="http://www.w3.org/ns/ttml#parameter">
>>>      <features xml:base="http://www.w3.org/ns/ttml/feature/">
>>>        <feature value="prohibited">#fontStyle-italic</feature>
>>>        <feature value="use">#fontStyle-bold</feature>
>>>      </features>
>>>     <extensions xml:base="http://example.noname/profile1">
>>>         <ttp:extension
>>> value="required">#prefilter-by-language</ttp:extension>
>>>     </ttp:extensions>
>>> </contentprofile>
>>>
>>> > @contentProfile
>>>
>>> What about a list of one or more content profile designator URIs,
>>> each indicating conformance to a content profile, e.g.
>>>
>>> <tt ttp:contentProfile="http://example.noname/profile1
>>> http://example.noname/profile2">
>>>
>>> Best,
>>>
>>> -- Pierre
>>>
>>> On Thu, Jul 11, 2013 at 9:16 AM, Timed Text Working Group Issue
>>> Tracker <sysbot+tracker@w3.org> wrote:
>>> > ISSUE-261: signaling docoument profile conformance is separate from
>>> > decoder presentation requirements [TTML.next]
>>> >
>>> > http://www.w3.org/AudioVideo/TT/tracker/issues/261
>>> >
>>> > Raised by: Mike Dolan
>>> > On product: TTML.next
>>> >
>>> > The profile element and attribute currently signal a feature set
>>> > that a decoder must implement in order to reasonably present the
>>> > document. Although it also hints at what features the document
>>> > instance may include, it does not signal document instance conformance
> today.
>>> >
>>> > There is currently no mechanism to signal what profile a document
>>> > instance conforms to (e.g. sdp-us).
>>> >
>>> > It is desirable to add this capability to TTML. However, simply
>>> > adding this semantic to the existing profile element and attribute
>>> > overly constrains the existing (decoder) and desired (document)
>>> > semantics. It is unreasonable to require that the single element
>>> > and attribute simultaneously signal both. For example, the fact
>>> > that a document instance conforms to dfxp-full does and should not
>>> > automatically infer that an sdp-us decoder could not properly
>>> > present it. That is instance dependent. This situation is aggravated
> when multiple profiles are involved.
>>> >
>>> > Some means must be defined to separately signal these different
>>> > semantics. For example, we could create a new element and attribute
>>> > - <ContentProfile> and contentProfile.
>>> >
>>> >
>>> >
>>> >
>>>
>>
>
>

Received on Friday, 12 July 2013 20:46:23 UTC