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

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
>>>>
>>>>
>>>>
>>>>