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From: wolfgang.berndorfer
Date: Fri, Sep 02 2022 7:29AM
Subject: Captions not in Text-Format
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Captions may be provided in a caption-file OR as pure graphic in a video.
The definition says: "synchronized visual and/OR text alternative."

So pure graphical captions pass SC 1.2.2 and 1.2.4.



But what about people who are hard of hearing AND visually impaired?

And what about SR users who want to find out the correct spelling of an
unknown term or name?



"For optimum accessibility, provide a separate caption file of the
description of visual information."

( <https://www.w3.org/WAI/media/av/captions/>
https://www.w3.org/WAI/media/av/captions/)



1. Are graphical captions an issue for SC 1.4.5 Images of text? Neither the
Understanding examples nor techs suggest that.

2. Is there any other SC that covers the problem?

3. Is a caption file (WebVTT, .) the obvious text alternative regarding to
SR support?



Thanks for clarification!



Wolfgang

From: Steve Green
Date: Fri, Sep 02 2022 8:39AM
Subject: Re: Captions not in Text-Format
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The WCAG definition of captions includes images of text embedded in video. The WCAG definition of an image of text states "text that has been rendered in a non-text form (e.g., an image)", which obviously fails the level AA success criterion 1.4.5 (Images of Text) even though the definition does not specifically mention video content. If you are only aiming to meet WCAG level A, this does not matter.
See https://www.w3.org/TR/WCAG21/#dfn-captions and https://www.w3.org/TR/WCAG21/#dfn-images-of-text

The WCAG level AAA success criterion 1.2.8 is specifically designed to address the requirements of people with both visual and hearing impairments. It requires that you provide all of the information in the synchronized media (both visual and auditory) in text form, presumably because this can be used with appropriate output devices such as Braille displays.

The WebVTT file would not usually be sufficient to meet SC 1.2.8 because it is not likely to contain the information that is presented visually in the video. The file also contains all the timing information, which would result in a lot of noise for screen reader users whether they are using audio output or a Braille display.

Steve Green
Managing Director
Test Partners Ltd

From: wolfgang.berndorfer
Date: Sat, Sep 03 2022 4:57AM
Subject: Re: Captions not in Text-Format
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Thank you, Steve for clarification concerning SC 1.4.5 and the hint to SC 1.2.8!

So, caption files seem to be the solution for the realization of captions. Or are there any other mechanisms to pass 1.4.5 in videos?

And what do we know about captions for SR users?

In my third question I didn't mean that the caption file should be read with the SR, just like I do not read the HTML Code. My question is, how these files are rendered and supported by UA/AT.

I just started to learn about WebVTT and tried out the first example that Google brought:
https://brenopolanski.github.io/html5-video-webvtt-example/
I found a way in Chrome with JAWS to navigate to the caption text. Don't ask me how I found the captions again after pressing pause or play…

There seems to be no mechanism available to jump to a caption in JAWS and NVDA. And a mechanism that puts out the current caption at my braille display, while I listen to a video, has to be found yet.

Are captions underestimated by AT?

Wolfgang

From: Steve Green
Date: Sun, Sep 04 2022 1:37AM
Subject: Re: Captions not in Text-Format
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The WCAG level A and AA success criteria are designed for people who either have a visual impairment or a hearing impairment, but not both. Therefore neither the captions nor the caption files are intended for screen reader users at level AA, so it is not surprising that there is no way to read them. Are there any media players that do allow captions to be read?

At WCAG level AAA, success criterion 1.2.8 requires that you provide all of the visual and auditory information in text form, so there is no need to interact with the media player at all.

There is an issue with regard to SC 1.4.5 (Images of Text) that I had not considered before. Open captions clearly fail this success criterion, but what if closed captions have been implemented in a media player that does not allow any customisation of the captions' appearance? Arguably, the captions are effectively no more than images of text.

Steve

From: wolfgang.berndorfer
Date: Mon, Sep 05 2022 12:46AM
Subject: Re: Captions not in Text-Format
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Again example https://brenopolanski.github.io/html5-video-webvtt-example/:
... is embedded as <video> and the captions implemented with <track />.
https://html.spec.whatwg.org/multipage/media.html#the-track-element

I tested in Chrome 105 and Jaws/Fusion 2022:
When the video shows subtitles, there is a text found by the SR, e.g. " Aprendi a me virar e você volto".
So the captions are rendered as text and can be found with a SR though not as easy as I wished.

> The WCAG level A and AA success criteria are designed for people who either have a visual impairment or a hearing impairment, but not both. Therefore neither the captions nor the caption files are intended for screen reader users at level AA, so it is not surprising that there is no way to read them.

Why not surprising? Screen readers may and do perform more than WCAG requires.
;-)

From: Karen McCall
Date: Tue, Sep 06 2022 7:27AM
Subject: Re: Captions not in Text-Format
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Although not directly related to this discussion, ISO does have a guide/standard on captions and subtitles.

As someone who uses a screen reader, having subtitles for films in a different language is most useful .

Things get a bit tricky if the film is in a different language and you have or want both subtitles translating the audio and captions to provide text in the language of the film. Then you add video description on top of that.

https://www.iso.org/standard/69060.html

I recognize that in some areas, captions and subtitles are used interchangeably or subtitles is used to describe captions. It can get quite confusing. 😊

Cheers, Karen

From: wolfgang.berndorfer
Date: Tue, Sep 06 2022 9:41AM
Subject: Re: Captions not in Text-Format
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Karen, could you please describe a little bit, how you achieve captions with your screen reader?
I didn't find a way to get the current captions displayed in braille.

A good performance would be an argument for a way to implement captions for SR-users.

From: Karen McCall
Date: Tue, Sep 06 2022 9:47AM
Subject: Re: Captions not in Text-Format
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I wrote a book a couple of years ago to demonstrate the inaccessibility of multimedia in PDF content. In the source document I had to create a structure of headings to allow those of us using screen readers to get close to the multimedia and then provide instructions on how to locate the player/video and begin playing the video. It was a disaster, even with the additional supports I created.

The videos I used weren't captioned. Typically captions are thought of for people who are deaf or hard of hearing, not those of us who might be deafblind. I think this is a gap in understanding disability and the broad range of disabilities. It also demonstrates that we think of solutions as linear, for a disability, rather than seeing the bigger picture.

I don't use a Braille display so can't answer your question. I don't even know if a screen reader can consistently access captions or subtitles in video content generally, in any environment.

I'll see if I can find any resources on this and get back to you.

Cheers, Karen

From: Karen McCall
Date: Tue, Sep 06 2022 9:55AM
Subject: Re: Captions not in Text-Format
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A search gives the result that accessing captions is inconsistent, you have to be really fast with the keyboard and the text "if you're lucky" keeps appearing with instructions on how to access captions in videos with a screen reader.

So, subtitles for content in a different language and captions are still not "seen" as something someone who uses a screen reader "needs" access to.

I have one more place to check but am not confident the answer will be a positive one.

Cheers, Karen

From: Murray Inman
Date: Tue, Sep 06 2022 3:11PM
Subject: Re: Captions not in Text-Format
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Wolfgang,
Good browser support for using <video>, <audio>, and <track> elements is
very minimal and is often frustrating for many AT users. I suggest taking a
look at the open source AblePlayer project
<https://github.com/ableplayer/ableplayer#able-player> from Terrill
Thompson and the University of Washington. If you have the freedom to use
this javascript library, it will find specifically classed audio and video
elements along with their accompanying tracks and render a nice, generally
accessible video player. It isn't perfect, but it is well thought out and
we get positive feedback about using it.

It will automatically handle any caption and description type WebVTT tracks
that are provided. We often will have one VTT file that provides timed
captions and one VTT that provides timed audio description text. If the
user turns on the audio description through the player interface, it uses
the well-supported speech APIs in the browser to speak the text. One of the
screen reader users on my team would often use the transcript feature that
displays both captions and descriptions together in a separate area and use
his screen reader to read the entire transcript faster than it could play.

I hope this helps.

Murray Inman
Manager, Instructional Media and Accessibility
Rio Salado College | https://riosalado.edu


On Tue, Sep 6, 2022 at 8:55 AM Karen McCall < = EMAIL ADDRESS REMOVED = > wrote:

> A search gives the result that accessing captions is inconsistent, you
> have to be really fast with the keyboard and the text "if you're lucky"
> keeps appearing with instructions on how to access captions in videos with
> a screen reader.
>
> So, subtitles for content in a different language and captions are still
> not "seen" as something someone who uses a screen reader "needs" access to.
>
> I have one more place to check but am not confident the answer will be a
> positive one.
>
> Cheers, Karen
>
>

From: Kevin Prince
Date: Wed, Sep 07 2022 7:14AM
Subject: Re: Captions not in Text-Format
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Really pleased top see deafblindness getting some attention as a unique impairment her. I have nothing to offer at this level other than my thanks for a fascinating thread that I would like to summarise and share with the Board in due course. If there is anyone who might be persuaded to join us on a call at some point in the future (we are NZ timezone but flexible) I think that there is some valuable insight to feed our advocacy work.

Kevin Prince

Wearing his Deafblind Association NZ hat.
Kevin Prince
Product Accessibility & Usability Consultant

From: wolfgang.berndorfer
Date: Wed, Sep 07 2022 10:23AM
Subject: Re: Captions not in Text-Format
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Hi Murray,

Very interesting to know that there is a development of a player with essential features for SR users. Thank you for the information, I will take a look.

But for the community it would be necessary that such features get available in standard browsers.

It is good to see that the community points out their needs. Thanks to Karen and Kevin!