WebAIM - Web Accessibility In Mind

E-mail List Archives

Re: Captions not in Text-Format

for

From: Murray Inman
Date: Sep 6, 2022 3:11PM


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 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
>
> -----Original Message-----
> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of
> <EMAIL REMOVED>
> Sent: Tuesday, September 6, 2022 11:42 AM
> To: 'WebAIM Discussion List' < <EMAIL REMOVED> >
> Subject: Re: [WebAIM] Captions not in Text-Format
>
> 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.
>
> -----Original Message-----
> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of
> Karen McCall
> Sent: Tuesday, September 6, 2022 3:27 PM
> To: WebAIM Discussion List < <EMAIL REMOVED> >
> Subject: Re: [WebAIM] Captions not in Text-Format
>
> 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://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.iso.org%2Fstandard%2F69060.html&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131242892%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=uSvw6FUfQPV0TGXadtdsumRYQydAF72QKElDp5G6A6M%3D&amp;reserved=0
>
> 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
>
> -----Original Message-----
> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of
> <EMAIL REMOVED>
> Sent: Saturday, September 3, 2022 6:58 AM
> To: 'WebAIM Discussion List' < <EMAIL REMOVED> >
> Subject: Re: [WebAIM] Captions not in Text-Format
>
> 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://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbrenopolanski.github.io%2Fhtml5-video-webvtt-example%2F&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131242892%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=O1%2BpU0V8Pb3pQKi5Z59bMw834bsT0sLFmEdLkySRbg8%3D&amp;reserved=0
> 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
>
>
> -----Original Message-----
> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of
> Steve Green
> Sent: Friday, September 2, 2022 4:40 PM
> To: WebAIM Discussion List < <EMAIL REMOVED> >
> Subject: Re: [WebAIM] Captions not in Text-Format
>
> 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://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.w3.org%2FTR%2FWCAG21%2F%23dfn-captions&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=XHL%2FzrfVFK2BOOF3guYBWoG26SoLt7f%2B8B5nnqkgufQ%3D&amp;reserved=0
> and
> https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.w3.org%2FTR%2FWCAG21%2F%23dfn-images-of-text&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=o1vWKq6hFKj4HEFifmmbmLwYNA9hhGxkzBrFVZl8y1g%3D&amp;reserved=0
>
> 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
>
>
> -----Original Message-----
> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of
> <EMAIL REMOVED>
> Sent: 02 September 2022 14:30
> To: 'WebAIM Discussion List' < <EMAIL REMOVED> >
> Subject: [WebAIM] Captions not in Text-Format
>
> 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://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.w3.org%2FWAI%2Fmedia%2Fav%2Fcaptions%2F&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=%2Fsvj5zP83dv7ayevk1z%2BJjQALUhMlX0mwctoKZPclPw%3D&amp;reserved=0
> >
>
> https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.w3.org%2FWAI%2Fmedia%2Fav%2Fcaptions%2F&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=%2Fsvj5zP83dv7ayevk1z%2BJjQALUhMlX0mwctoKZPclPw%3D&amp;reserved=0
> )
>
>
>
> 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
>
> > > https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Flist.webaim.org%2F&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=2MR73SnVdmeVTg7LGRpIsmPgaMZ8S1fKn46tPhCFsc4%3D&amp;reserved=0
> List archives at
> https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwebaim.org%2Fdiscussion%2Farchives&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=wV3BX%2BOE2pPcB9RNQDtz1qT7a%2BNtc8iAluoPsXhlapY%3D&amp;reserved=0
> > > > https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Flist.webaim.org%2F&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=2MR73SnVdmeVTg7LGRpIsmPgaMZ8S1fKn46tPhCFsc4%3D&amp;reserved=0
> List archives at
> https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwebaim.org%2Fdiscussion%2Farchives&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=wV3BX%2BOE2pPcB9RNQDtz1qT7a%2BNtc8iAluoPsXhlapY%3D&amp;reserved=0
> >
> > > https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Flist.webaim.org%2F&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=2MR73SnVdmeVTg7LGRpIsmPgaMZ8S1fKn46tPhCFsc4%3D&amp;reserved=0
> List archives at
> https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwebaim.org%2Fdiscussion%2Farchives&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=wV3BX%2BOE2pPcB9RNQDtz1qT7a%2BNtc8iAluoPsXhlapY%3D&amp;reserved=0
> > > > https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Flist.webaim.org%2F&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=2MR73SnVdmeVTg7LGRpIsmPgaMZ8S1fKn46tPhCFsc4%3D&amp;reserved=0
> List archives at
> https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwebaim.org%2Fdiscussion%2Farchives&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=wV3BX%2BOE2pPcB9RNQDtz1qT7a%2BNtc8iAluoPsXhlapY%3D&amp;reserved=0
> >
> > > https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Flist.webaim.org%2F&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=2MR73SnVdmeVTg7LGRpIsmPgaMZ8S1fKn46tPhCFsc4%3D&amp;reserved=0
> List archives at
> https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwebaim.org%2Fdiscussion%2Farchives&amp;data%7C01%7C%7C87ea0a13f7be48401fb008da901e4ff4%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637980757131399114%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=wV3BX%2BOE2pPcB9RNQDtz1qT7a%2BNtc8iAluoPsXhlapY%3D&amp;reserved=0
> > > > > >