APA WG comment: Add note on alt text

[michael-n-cooper]

With respect to the 7.12.2 altText named metadata item, this is directly related to the accessibility requirement of having an alternate text version for images (Success Criterion 1.1.1 Non-text Content). Could you add a note here saying something like:

Note:
Authors are encouraged to provide text alternatives for every non-decorative image and/or compound image set by using the altText named metadata item. This is necessary for making the image in the document accessible to persons with (visual) disabilities, thus complying with
https://www.w3.org/TR/2018/REC-WCAG21-20180605/#non-text-content WCAG 2.1 success criterion 1.1.1 (Non-text content).

[css-meeting-bot]

The Timed Text Working Group just discussed APA WG comment: Add note on alt text, and agreed to the following:

• SUMMARY: Discussed in call today. The editor will consider the best location to incorporate this advice for document authors

The full IRC log of that discussion

<cyril_> Topic: APA WG comment: Add note on alt text
<cyril_> github: https://github.com//issues/521
<cyril_> pal: the text that is being suggested might already be in 5.1
<cyril_> ... I can take an action item to determine if the text is already present and if not, add it to the annex D
<cyril_> nigel: they wanted to specifically put it in the altText section
<cyril_> pal: we should not put where the syntax is defined but I'm happy to go through the document to make sure the concept is in
<cyril_> pal: that note is actually best handled in annex D when we describe how to meet the criteria
<cyril_> nigel: makes sense
<cyril_> SUMMARY: Discussed in call today. The editor will consider the best location to incorporate this advice for document authors

[palemieux]

@michael-n-cooper In IMSC, altText is not the means for offering a text-based alternative experience to the consumer, when image-based subtitles and captions are offered. Instead a separate text-based subtitle or caption document is offered, and so the term necessary does not seem appropriate here. What about modifying the note at 5.1 along the lines of the following:

The altText named metadata item also allows text equivalent string to be associated with an image. This allows, for example, indexation of the content, matching actual image contents to intended contents during quality checking of the document, and making the image in the document accessible to persons with (visual) disabilities during authoring.

ED: Clarified that altText is not intended for the ultimate consumer of the timed text content.

[palemieux]

See also #321

[gzimmermann]

What about the following note, based on the proposal by @palemieux :
"The altText named metadata item also allows a text equivalent string to be associated with an image. This allows, for example, indexation of the content, matching actual image contents to intended contents during quality checking of the document, and making the image in the document accessible to timed text authors with (visual) disabilities. Note that, for offering a text-based alternative experience to the consumer, a separate text-based subtitle or caption document is necessary."

[css-meeting-bot]

The Timed Text Working Group just discussed APA WG comment: Add note on alt text imsc#521, and agreed to the following:

• SUMMARY: Continue discussion by review of the pull request w3c/imsc#542

The full IRC log of that discussion

<nigel> Topic: APA WG comment: Add note on alt text imsc#521
<nigel> github: https://github.com//issues/521
<nigel> Nigel: @gzimmermann proposed some text.
<nigel> Pierre: I opened a pull request a few minutes ago.
<nigel> .. I didn't duplicate the proposal verbatim because some of it was already in the paragraph above.
<nigel> .. I did use the term consumer to contrast with the note about authors.
<nigel> SUMMARY: Continue discussion by review of the pull request #542

[palemieux]

@gzimmermann See #542. The last sentence of the note at #521 (comment) is integrated in the paragraph above the note.

[gzimmermann]

Okay with me.

[michael-n-cooper]

APA agrees with disposition.

[michael-n-cooper]

Re-adding a11y-needs-resolution label because of new information about how the horizontal review tracker works, but this is still signed off from APA.