Native support for the longdesc attribute in Chrome

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Laura Carlson

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Mar 27, 2013, 9:32:34 AM3/27/13
to Dominic Mazzoni, Chromium Accessibility
Hi Dominic,

Is this the best place to ask that Chrome please add native support
for the longdesc attribute?

Longdesc is a valid HTML5 attribute. HTML Image Description Extension
specification has been published:
http://www.w3.org/News/2013.html#entry-9756

The W3C validator http://validator.w3.org was updated last week to
support the longdesc attribute as specified in
http://www.w3.org/TR/html-longdesc/

The browser should supply a way of accessing a longdesc according to the spec:

"
User agents should make the link available to all users through the
regular user interface.

User agents should expose the link to relevant APIs, especially
accessibility-oriented APIs.

User agents should enable users to discover when images in a page
contain a long description.
"
http://www.w3.org/TR/2013/WD-html-longdesc-20130312/#longdesc

Opera added native support for longdesc in 2009.
http://www.opera.com/docs/changelogs/mac/1010b1/#ui
iCab has had native support for longdesc long before then.

Innovative browser vendors provide ways that make longdesc discoverable:
http://www.d.umn.edu/~lcarlson/research/ld-ua.html

HTML 4 on longdesc
http://www.w3.org/html/wg/wiki/ChangeProposals/InstateLongdesc/References#HTML_4_on_longdesc

Chris Kennish released a Chrome plugin providing image highlighting
and right-click access to longdesc. It is available at:
https://chrome.google.com/webstore/detail/longdesc/haohljalgapbacpkfefnmhiadanhejmb

Thank you.

Best Regards,
Laura

--
Laura L. Carlson

Dominic Mazzoni

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Mar 27, 2013, 11:11:19 AM3/27/13
to Laura Carlson, Chromium Accessibility
Laura,

Yes, this is a great list to discuss longdesc in Chrome. Now that the spec has been published I think we can add it.

Adding support to longdesc for assistive technology should be straightforward, especially on Windows where some screen readers already support it. I filed: http://crbug.com/224287

Making longdesc available to all users through the regular user interface sounds good, I think a good place to start would be to add it to the context menu. I filed: http://crbug.com/224285

I don't think it would fly to add a visual decoration for images with longdesc unless we could give the page author a way to customize its style and come up with a solution that works on mobile, too.

- Dominic

Laura Carlson

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Mar 27, 2013, 11:46:05 AM3/27/13
to Dominic Mazzoni, Chromium Accessibility, Chris Kennish, Charles McCathieNevile
Hi Dominic,

On Wed, Mar 27, 2013 at 10:11 AM, Dominic Mazzoni <dmaz...@chromium.org> wrote:
> Laura,
>
> Yes, this is a great list to discuss longdesc in Chrome. Now that the spec
> has been published I think we can add it.

That's terrific. Thank you very much.

> Adding support to longdesc for assistive technology should be
> straightforward, especially on Windows where some screen readers already
> support it. I filed: http://crbug.com/224287
>
> Making longdesc available to all users through the regular user interface
> sounds good, I think a good place to start would be to add it to the context
> menu. I filed: http://crbug.com/224285

Thank you for filing these bugs.

> I don't think it would fly to add a visual decoration for images with
> longdesc unless we could give the page author a way to customize its style

Yes. That is important. The spec has a "No visual encumbrance"
requirement so supplying user option would be needed.
http://www.w3.org/TR/2013/WD-html-longdesc-20130312/#req

For example Chris Kennish's longdesc chrome plugin provides an array
of longdesc highlighting preferences including having no highlight:
https://chrome.google.com/webstore/detail/longdesc/haohljalgapbacpkfefnmhiadanhejmb

Once the extension is installed if a user selects

1. Preferences
2. Extensions
3. Then under Longdesc 0.0.1 Select: The "Options" Link. They are
presented with an array of options:

Highlight color:
* red
* green
* blue
* yellow
* aqua
* black
* fuchsia
* gray
* lime
* maroon
* navy
* olive
* purple
* silver
* teal
* white

Highlight style:
* solid
* dotted
* inset
* outset

Highlight width:
* 1
* 2
* 3
* 5
* 0 (no highlight)

Open longdesc:
* same tab
* new tab
* new window

> and come up with a solution that works on mobile, too.

A User Interface idea that has been discussed for touch devices is a
"turn the image around" transition e.g., the UI could have a flip
transition: akin to flipping over a hard-copy physical photograph to
read what is written on the back. Activation could be upon a finger
flick gesture on the corner of an image or a tap-and-hold gesture for
a touch device contextual menu.

Best Regards,
Laura
--
Laura L. Carlson

Charles McCathie Nevile

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Mar 27, 2013, 9:40:22 PM3/27/13
to Dominic Mazzoni, Laura Carlson, Chromium Accessibility, Chris Kennish
Hi all,

On Wed, 27 Mar 2013 16:46:05 +0100, Laura Carlson
<laura.le...@gmail.com> wrote:

> On Wed, Mar 27, 2013 at 10:11 AM, Dominic Mazzoni
>> Yes, this is a great list to discuss longdesc in Chrome. Now that the
>> spec has been published I think we can add it.
>
> That's terrific. Thank you very much.

Yes, I would love to see this. (It would be the easiest way for me to get
support into Yandex' browser :) ).

>> Adding support to longdesc for assistive technology should be
>> straightforward, especially on Windows where some screen readers already
>> support it. I filed: http://crbug.com/224287
>>
>> Making longdesc available to all users through the regular user
>> interface sounds good, I think a good place to start would be to add it
>> to the context menu. I filed: http://crbug.com/224285

Yes, that is a sensible thing to do - and what Chris' extension does. The
only difference in Opera is that the entire menu item is only there when
there is a longdesc.

> Thank you for filing these bugs.
>
>> I don't think it would fly to add a visual decoration for images with
>> longdesc unless we could give the page author a way to customize its
>> style
>
> Yes. That is important.

Right.

> The spec has a "No visual encumbrance"
> requirement so supplying user option would be needed.
> http://www.w3.org/TR/2013/WD-html-longdesc-20130312/#req
>
> For example Chris Kennish's longdesc chrome plugin provides an array
> of longdesc highlighting preferences including having no highlight...

My extension (I can give you the code, but it is pretty ugly and has a big
bug still) takes a slightly different approach and adds an indicator to
the address bar when there is a longdesc present. That is clickable, and
the dropdown is a list of the images linked to the longdescs.

I think at least a styling option is useful. For voice it's easier to use
something like img[longdesc]::before {…} but I agree that the visual thing
is tricky in a visual browser.

>> and come up with a solution that works on mobile, too.
>
> A User Interface idea that has been discussed for touch devices is a
> "turn the image around" transition e.g., the UI could have a flip
> transition: akin to flipping over a hard-copy physical photograph to
> read what is written on the back. Activation could be upon a finger
> flick gesture on the corner of an image or a tap-and-hold gesture for
> a touch device contextual menu.

Yes, there are various ideas about putting something on top of the image
as an indicator that would work for mobile. When notin fullscreen mode my
opera extension actually worked with their mobile extensions framework -
but in fullscreen mode you couldn't see the indicator.

Anyway, it's not a solved problem how to do this really well on small
mobile interfaces. More implementation and more experience would teach us
more about it...

cheers

Chaals
Charles McCathie Nevile - Consultant (web standards) CTO Office, Yandex
cha...@yandex-team.ru Find more at http://yandex.com

Laura Carlson

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Apr 22, 2013, 1:21:12 PM4/22/13
to Chromium Accessibility, Dominic Mazzoni, Chris Kennish, Charles McCathie Nevile
Hi all,

Some longdesc test cases are at:
http://www.d.umn.edu/~lcarlson/research/ld-tests/tests/

They include the following 4 tests and expected results.

1. longdesc on a different page using an absolute URL:
http://www.d.umn.edu/~lcarlson/research/ld-tests/tests/index.html#ld1

2. longdesc on a different page using a relative URL:
http://www.d.umn.edu/~lcarlson/research/ld-tests/tests/index.html#ld2

3. longdesc on the same page using a fragment identifier:
http://www.d.umn.edu/~lcarlson/research/ld-tests/tests/index.html#ld3

4. longdesc as a descendant of an <a> element:
http://www.d.umn.edu/~lcarlson/research/ld-tests/tests/index.html#ld4

Expected results are at:
http://www.d.umn.edu/~lcarlson/research/ld-tests/tests/index.html#results

Charles McCathie Nevile

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Apr 22, 2013, 9:14:24 AM4/22/13
to Chromium Accessibility, Laura Carlson, Dominic Mazzoni, Chris Kennish
I've got another one that uses a data URI. Attached to save time, but at
some point soon I need to get all these into the HTML repository anyway,
so feel free to nag me in the hope that I get off my backside sooner...

cheers

Chaals
datauritest.html

Laura Carlson

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Apr 25, 2013, 12:58:30 PM4/25/13
to Charles McCathie Nevile, Chromium Accessibility, Dominic Mazzoni, Chris Kennish
Hi Chaals,

Thanks. I neglected to add a data URI longdesc test.

It is now added as test case 5:
http://www.d.umn.edu/~lcarlson/research/ld-tests/tests/index.html#ld5

I also linked it to Chromium Issue 224285.

> so feel free to nag me in the hope that I get off my backside sooner...

Will do :-)

Best Regards,
Laura
--
Laura L. Carlson

Laura Carlson

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Jul 22, 2013, 7:50:48 AM7/22/13
to Dominic Mazzoni, Chromium Accessibility, Vlad Alexander, Chris Kennish, Charles McCathie Nevile, John Foliot, Catherine Roy, Adrian Roselli, Mike Gifford, Denis Boudreau, David MacDonald, Henry G, Karl Groves, Mike Reiser, Monika Trebo, Nigel Peck, Ryan Benson, Leif Halvard Silli, alvaro domingo zurdo, Harry Loots, Halena Rojas
Hi Dominic,

Over 100 people have taken time (by starring and commenting) to ask
Google to support the HTML longdesc attribute [1] by fixing the Chrome
bugs that you so kindly filed last March [2] [3].

As the person who first asked [4] that Chrome support longdesc and on
behalf of those who have taken the time to star and comment the
issues, I am following up to find out what the next steps are? Could
these bugs be assigned now to a Chromium developer? People are asking
when we can expect to see longdesc support in Chrome.
http://code.google.com/p/chromium/issues/detail?id=224285#c19

If you require testing, please let me know and I can organize this.

Thank you in advance,
Laura

[1] http://www.w3.org/TR/html-longdesc/
[2] http://crbug.com/224285
[3] http://crbug.com/224287
[4] http://groups.google.com/a/chromium.org/group/chromium-accessibility/browse_thread/thread/6542ed13863a8f2c#
--
Laura L. Carlson

Dominic Mazzoni

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Jul 22, 2013, 7:25:00 PM7/22/13
to Laura Carlson, Chromium Accessibility, Vlad Alexander, Chris Kennish, Charles McCathie Nevile, John Foliot, Catherine Roy, Adrian Roselli, Mike Gifford, Denis Boudreau, David MacDonald, Henry G, Karl Groves, Mike Reiser, Monika Trebo, Nigel Peck, Ryan Benson, Leif Halvard Silli, alvaro domingo zurdo, Harry Loots, Halena Rojas
Hi Laura,

Thanks for your work advocating for this feature. I just uploaded an initial draft of an implementation for code review. Please be patient as the code review process could take some time - but I'm committed to getting this implemented soon.

To everyone receiving this email - in the future, I'd appreciate it if people could star bugs as a way to vote for them. Posting comments that say "me too" just makes it harder for developers to find the useful technical information in the bug. Posting additional relevant technical information is always helpful, of course!

One thing that might be helpful in this case: if you are aware of any prominent or mainstream websites that already use longdesc anywhere, an example url would be great. I know this is a bit of a chicken-and-egg problem, but since Firefox is exposing longdesc in the context menu, if by any chance there are any websites already taking advantage of it then it'd be great to point that out on the bug.

Also, I'd love to know what other Chrome accessibility features you'd like us to prioritize. Please start a new thread with any ideas you have!

- Dominic

Laura Carlson

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Jul 23, 2013, 7:31:43 AM7/23/13
to Dominic Mazzoni, Chromium Accessibility, Vlad Alexander, Chris Kennish, Charles McCathie Nevile, John Foliot, Catherine Roy, Adrian Roselli, Mike Gifford, Denis Boudreau, David MacDonald, Henry G, Karl Groves, Mike Reiser, Monika Trebo, Nigel Peck, Ryan Benson, Leif Halvard Silli, alvaro domingo zurdo, Harry Loots, Halena Rojas
Hi Dominic,

> Thanks for your work advocating for this feature. I just uploaded an
> initial draft of an implementation for code review. Please be patient as
> the code review process could take some time - but I'm committed to getting
> this implemented soon.

Excellent! Deepest thanks to you.

> To everyone receiving this email - in the future, I'd appreciate it if
> people could star bugs as a way to vote for them. Posting comments that say
> "me too" just makes it harder for developers to find the useful technical
> information in the bug. Posting additional relevant technical information
> is always helpful, of course!

Indeed.

> One thing that might be helpful in this case: if you are aware of any
> prominent or mainstream websites that already use longdesc anywhere, an
> example url would be great. I know this is a bit of a chicken-and-egg
> problem, but since Firefox is exposing longdesc in the context menu, if by
> any chance there are any websites already taking advantage of it then it'd
> be great to point that out on the bug.

Yes, as Chaals mentioned I started a page some time ago, which no
doubt has link rot. I can run it through a link checker. Anyone who
has additional examples Please let me know and I'll add them.

> Also, I'd love to know what other Chrome accessibility features you'd like
> us to prioritize. Please start a new thread with any ideas you have!

Discoverability for longdesc would be great.
http://www.d.umn.edu/~lcarlson/research/ld-ua.html

Thank you from the bottom of my heart, Dominic, for your dedicated commitment.

mctu...@gmail.com

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Jul 24, 2013, 5:35:22 PM7/24/13
to chromium-ac...@chromium.org
On Tuesday, 23 July 2013 00:25:00 UTC+1, Dominic Mazzoni wrote:
 
One thing that might be helpful in this case: if you are aware of any prominent or mainstream websites that already use longdesc anywhere, an example url would be great. I know this is a bit of a chicken-and-egg problem, but since Firefox is exposing longdesc in the context menu, if by any chance there are any websites already taking advantage of it then it'd be great to point that out on the bug.

There's some data collected by Steve Faulkner from the "Top 10000 web sites home pages" last year linked here:

http://lists.w3.org/Archives/Public/public-html-a11y/2012Sep/0295.html

And some brief analysis here:

http://lists.w3.org/Archives/Public/public-html/2012Sep/0312.html

The latest data dump is available from http://webdevdata.org/

The list of longdesc examples in the wild compiled by the HTML-A11Y-TF is here:

http://www.d.umn.edu/~lcarlson/research/ld.html

Some brief analysis here:

http://lists.w3.org/Archives/Public/public-html-a11y/2012Sep/0463.html

-Matt


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