Re: Why is there no alt attribute associated with the poster attribute on a video element (or, what's the accessible name calculation on a video element

Hi Silvia,

Depreciating the @poster attribute and creating the <poster> element with
alt attribute also makes sense.

Who is ''THE PERSON'' that we need to discuss this with? Do you have any
idea?



On Tue, May 19, 2020 at 3:02 PM John Foliot <john.foliot@deque.com> wrote:

> Hi Thrishma,
>
> The problem is an architectural one: you cannot attach an attribute to
> another attribute (and @poster is just that, an attribute).
>
> We have two visual assets: one that moves (the mp4) and one that does not
> (the jpg/png/"poster') - both will potentially require text alternatives.
>  The video itself will also require 2 types of textual alternative: likely
> a summarization of the video, as well as the captions which are actually
> the text equivalent for the *audio* track.
>
> The solution is to recognize that the poster is another related asset
> associated with the movie, but not always *part* of the movie. We already
> do that today with caption files and audio description files, where both
> are called as child elements of the parent <video> element.
>
> So, to really fix this and address the outstanding accessibility concern,
> the solution would be to deprecate the @poster attribute and instead create
> a <poster> element, which would be a different kind of child element (in
> the same way that <track> is today). That way, we could then do something
> like this:
>
> <video>
>
>     <track src="" kind="captions">
>
>     <track src="" kind="descriptions"> <!-- audio descriptions -->
>
>     <poster src="" alt="" aria-describedby=""> (and so on)
>
> </video>
>
> Respectfully,
>
> JF
>
> On Tue, May 19, 2020 at 10:32 AM thrishma reddy <thrishmareddy@gmail.com>
> wrote:
>
>> Hey Silvia,
>>
>> So to who do we ask/raise this issue for the alt attribute to be
>> included in the <video> tag?
>>
>> This issue has been open for years and I wish there is finally someone we
>> can reach out to who would actually solve this in 2020.
>>
>> Thanks,
>> Thrishma
>>
>>
>> On Mon, May 18, 2020 at 2:48 AM Silvia Pfeiffer <
>> silviapfeiffer1@gmail.com> wrote:
>>
>>> Hi Thrisma,
>>>
>>> Hmm.... you're right - it only has a "title" attribute.
>>> FWIW, I think it should have an explicit "alt" attribute.
>>>
>>> Just my 2c worth though.
>>>
>>> Cheers,
>>> Silvia.
>>>
>>>
>>> On Mon, May 18, 2020 at 8:02 AM thrishma reddy <thrishmareddy@gmail.com>
>>> wrote:
>>>
>>>> Hi Silvia,
>>>>
>>>> Thanks for your reply. So when you say alt attribute for the video do
>>>> you mean it looks like the below example?
>>>>
>>>> Example  -
>>>>
>>>> <video width="320" height="240" poster="/images/w3schools_green.jpg"
>>>> controls *alt="Bear catching a fish in a river"*>
>>>>    <source src="moviea.mp4" type="video/mp4">
>>>>    <source src="movaie.ogg" type="video/ogg">
>>>>    Your browser does not support the video tag.
>>>> </video>
>>>>
>>>> There is no example of the video's alt attribute that I could find on
>>>> the internet.
>>>>
>>>> I agree with you that there should be only one alternative field
>>>> describing the video. The poster  image is the visual summary and the alt
>>>> attribute is the textual summary of the video. There is no need to have an
>>>> alt attribute for the poster image as it's only purpose is to be a visual
>>>> summary of the video. This is true only when there exists an alt attribute
>>>> for the <video> tag as shown in the above example. Otherwise, the
>>>> poster property needs to have an alt attribute.
>>>>
>>>> Another question for you- When the source of an image is broken we
>>>> display the alt text of the <img> tag. Does the alt property (if
>>>> present) for the <video> tag do the same?
>>>>
>>>> Thanks,
>>>> Thrishma
>>>>
>>>> On Sun, May 17, 2020 at 4:56 PM Silvia Pfeiffer <
>>>> silviapfeiffer1@gmail.com> wrote:
>>>>
>>>>> Hey John,
>>>>>
>>>>> That's all a possibility, yes.
>>>>>
>>>>> So if your poster has different content from the video, your alt text
>>>>> should include the poster description, too, because it's supported by
>>>>> accessibility software. Introducing another attribute would require all
>>>>> accessibility software to be updated with two text alternatives for one
>>>>> element, which becomes very confusing very fast.
>>>>>
>>>>> Hope that helps.
>>>>>
>>>>> Best regards,
>>>>> Silvia.
>>>>>
>>>>> On Sun, May 17, 2020, 11:17 PM John Foliot <john.foliot@deque.com>
>>>>> wrote:
>>>>>
>>>>>> Silvia writes:
>>>>>>
>>>>>> > In essence: the poster is a visual summarisation of the video.
>>>>>>
>>>>>> Actually,  the poster  is  WAS ENVISIONED TO BE a visual
>>>>>> summarisation of the video, by the former HTML5 editor, who also
>>>>>> demonstrated on multiple occasions that he knew nothing of the
>>>>>> accessibility space: the needs, the users, their user experience, etc. and
>>>>>> he frequently demonstrated his lack of empathy in that regard.
>>>>>>
>>>>>> The reality is that the content author can point that @poster
>>>>>> attribute to ANY graphic image URI, including interstitials and/or
>>>>>> 'placeholder' slides (which may or may not contain "burned in" text
>>>>>> intended for the end-user) a reality that some engineers simply refuse to
>>>>>> accept as a possibility.
>>>>>>
>>>>>> Breaking this down:
>>>>>>
>>>>>> <video src="file.mp4"   <!-- this is a visual asset that requires a
>>>>>> text alternative, AKA an AccessibleName. Given its complexity, it also
>>>>>> needs an AccessibleDescription -->
>>>>>>
>>>>>>            poster="image.png">    <!-- this is a DIFFERENT visual
>>>>>> asset that also *potentially *requires a text alternative, AKA an
>>>>>> AccessibleName -->
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> > You only need one summary in text.
>>>>>>
>>>>>>
>>>>>> Respectfully, you are wrong. I do not know where or how you arrive at
>>>>>> this assertion, but it is simply and clearly wrong:
>>>>>>
>>>>>> *Success Criterion 1.1.1 Non-text Content (Level A)**:*
>>>>>> *All non-text content* that is presented to the user has a text
>>>>>> alternative that serves the equivalent purpose... (JF: ALL, not some)
>>>>>>
>>>>>> The text alternative is not a "summary", it is an alternative to the
>>>>>> visual representation. Any time there is an image with text burned into it
>>>>>> the textual alternative is not a summarization of that text: it must be
>>>>>> faithfully and accurately replicated in text that can be processed by
>>>>>> machine (i.e. a screen reader).
>>>>>>
>>>>>> Evidence for all of this was also brought forward "back in the day",
>>>>>> along with multiple impassioned and detailed explanations about this topic
>>>>>> by daily screen reader users. Please, listen to the end users - they know
>>>>>> better than a sighted engineer will ever understand what they need and want.
>>>>>>
>>>>>> JF
>>>>>>
>>>>>> On Fri, May 15, 2020 at 5:18 PM Silvia Pfeiffer <
>>>>>> silviapfeiffer1@gmail.com> wrote:
>>>>>>
>>>>>>> There were lengthy discussions about this back in the day - you
>>>>>>> should be able to Google them.
>>>>>>>
>>>>>>> In essence: the poster is a visual summarisation of the video. The
>>>>>>> video's alt tag is a text summarisation of the video. You only need one
>>>>>>> summary in text.
>>>>>>>
>>>>>>> Hope this helps.
>>>>>>>
>>>>>>> Best regards,
>>>>>>> Silvia.
>>>>>>>
>>>>>>>
>>>>>>> On Fri, May 15, 2020, 12:59 AM thrishma reddy <
>>>>>>> thrishmareddy@gmail.com> wrote:
>>>>>>>
>>>>>>>> Hello,
>>>>>>>>
>>>>>>>> I was wondering if there was ever any solution to the question
>>>>>>>> asked here - https://github.com/w3c/html/issues/1431 (Why is there
>>>>>>>> no alt attribute associated with the poster attribute on a video element
>>>>>>>> (or, what's the accessible name calculation on a video element)?
>>>>>>>>
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>> Thrishma
>>>>>>>>
>>>>>>>>
>>>>>>
>>>>>> --
>>>>>> *​John Foliot* | Principal Accessibility Strategist | W3C AC
>>>>>> Representative
>>>>>> Deque Systems - Accessibility for Good
>>>>>> deque.com
>>>>>> "I made this so long because I did not have time to make it shorter."
>>>>>> - Pascal
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>
> --
> *​John Foliot* | Principal Accessibility Strategist | W3C AC
> Representative
> Deque Systems - Accessibility for Good
> deque.com
> "I made this so long because I did not have time to make it shorter." -
> Pascal
>
>
>
>

Received on Saturday, 23 May 2020 13:02:41 UTC