Re: [Slim] Issue 43: How to know the modality of a language indication?

[Bernard Aboba <[e-mail]>]

Gunnar said:

"Applications not implementing such specific notations may use the
following simple deductions.

- A language tag in audio media is supposed to indicate spoken modality.

[BA] Even a tag with "Sign Language" in the description??

- A language tag in text media is supposed to indicate  written modality.

[BA] If the tag has "Sign Language" in the description, can this document
really say that?

- A language tag in video media is supposed to indicate visual sign
language modality except for the case when it is supposed to indicate a
view of a speaking person mentioned in section 5.2 characterized by the
exact same language tag also appearing in an audio media specification.

[BA] It seems like an over-reach to say that a spoken language tag in video
media should instead be interpreted as a request for Sign Language.  If
this were done, would it always be clear which Sign Language was intended?
And could we really assume that both sides, if negotiating a spoken
language tag in video media, were really indicating the desire to sign?  It
seems like this could easily result interoperability failure.

- A language tag in media where the modality is obvious or specified for
the media subtype definition is supposed to indicate that modality.
- A language tag in other media descriptions than above has undefined
modality."

On Sat, Oct 14, 2017 at 1:21 AM, Gunnar Hellström <
[e-mail]> wrote:

> Den 2017-10-14 kl. 04:25, skrev Randall Gellens:
>
>> At 1:46 PM -0700 10/13/17, Bernard Aboba wrote:
>>
>>  Issue 43 ( <https://trac.ietf.org/trac/slim/ticket/43>https://trac.ietf
>>> .org/trac/slim/ticket/43 ) results from a review comment that said that
>>> a simple way is required to decide if a language tag is a sign language or
>>> a written or spoken language.
>>>
>>>  Some applications scan the IANA language registry at startup for the
>>> word "Sign" in the tag description:
>>>
>>> <https://www.iana.org/assignments/language-subtag-registry/
>>> language-subtag-registry>https://www.iana.org/assignments/
>>> language-subtag-registry/language-subtag-registry
>>>
>>>
>>>  Currently, there are 319 language subtags that include "Sign Language"
>>> in their description.
>>>  Given the current layout of the language subtag registry, it is not
>>> clear to me that there is an easier way to determine which tags represent
>>> sign languages.  Nor is it within the SLIM WG charter to develop a
>>> modification to the language subtag registry to address this concern.
>>>  So I am wondering whether we might resolve this with a Note outlining
>>> the problem but not offering a solution.
>>>
>>
>> I think the wording in -14 addresses the comment by accepting Dale's
>> suggestion that, rather than know non-signed tags, it's the use of the
>> exact same tag in both an audio and a video stream that is the indicator.
>> That both tightens up the technical issue and simplifies it greatly.
>>
>> The only other instance where we might add such a note would be in 5.4:
>>
>> 5.4.  Undefined Combinations
>>
>>    With the exception of the case mentioned in Section 5.2 (an audio
>>    stream in parallel with a video stream with the exact same (spoken)
>>    language tag), the behavior when specifying a non-signed language tag
>>    for a video media stream, or a signed language tag for an audio or
>>    text media stream, is not defined.
>>
>> We could add your suggested note to 5.4.
>>
>> <GH>We can replace 5.4 with a more explicit section guiding applications
> to how to make the deduction simple. So, instead of a note, I suggest that
> we replace 5.4 with:
>
> 5.4 Relations between media and modality
> There is no easy way to deduct the intended modality from a language tag.
> Other specifications may introduce specific notations for modality used in
> a media or in relation to a language tag. Applications not implementing
> such specific notations may use the following simple deductions.
> - A language tag in audio media is supposed to indicate spoken modality.
> - A language tag in text media is supposed to indicate  written modality.
> - A language tag in video media is supposed to indicate visual sign
> language modality except for the case when it is supposed to indicate a
> view of a speaking person mentioned in section 5.2 characterized by the
> exact same language tag also appearing in an audio media specification.
> - A language tag in media where the modality is obvious or specified for
> the media subtype definition is supposed to indicate that modality.
> - A language tag in other media descriptions than above has undefined
> modality.
> ------------------------------------------------------------
> ---------------------------------------------------------
>
> My note:  by this we currently consciously exclude the following use and I
> am ok with that:
> -text in mp4 video
> -audio in mp4 video ( or is that only allowed in application/mp4 ??)
> -any modality in message media
> -most application media, however some may have explicit descriptions in
> subtype specifications.
>
> The exception with a view of a speaker stands out as very odd now,
> requiring comparison of language tags used in different media descriptions,
> and requiring simultaneous use of language in two different media that is
> otherwise out of scope for this draft. It was introduced while I still
> hoped that we could introduce other dependencies between language use in
> different media.  It is not the most urgent media/language combination to
> specify. It is also handled in draft-hellstrom-slim-modality-grouping.
> So, assuming that we can get progress on that draft, we could clean up the
> current draft by deleting the exception. I suggest that we delete the
> exception.
>
> /Gunnar
>
>
>
> --
> -----------------------------------------
> Gunnar Hellström
> Omnitor
> [e-mail]
> [phone]
>
>
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