Re: VTT/CSS (was RE: Evidence of 'Wide Review' needed for VTT)

Hi John

the question of how the user-agent makes it possible to follow these requirements is, I think, separate.  Yes, a UA can offer the ability to insert user style-sheets, or they could offer a more direct interface.

We probably need flexible ways for the content author to provide the styling they prefer; inline in the VTT file (in the header, in the cues), linked directly to the VTT file, or inherited from the environment (e.g. the page the video is playing in).  That’s what this question is about, I think.


> On Jan 19, 2015, at 17:32 , John Foliot <john@foliot.ca> wrote:
> 
> David Singer wrote:
>> 
>>> On Jan 19, 2015, at 15:39 , Jeroen Wijering wrote:
>>> 
>>> The one item I'm missing from the spec is inline CSS, but that's
>>> pushed to V2 right?
>> 
>> Sort-of.  I think that we can and should develop consensus on how to
>> handle it, and then a question of when it's integrated into the
>> bleeding-edge whatwg spec. is easy. whether we roll a 1.1 through the
>> Rec process is a separate question.
>> 
>>> (https://www.w3.org/Bugs/Public/show_bug.cgi?id=15023) On platforms
>>> like Flash or native Android, we'd like to have all cue styling
>> inline
>>> since there's no CSS. Publisher also need it when converting from
>>> legacy formats (608, TTML) into VTT. In these formats, the styling
>>> also "lives" inline.
>> 
>> when you say inline CSS, you mean both of
>> a) style-sheets in the header?
>> b) styling in the cues themselves, using CSS snippets?
>> 
>> Have you looked at the old threads on this question?  I think we got
>> close to a number of possible designs, but held off until it was really
>> needed and we had real implementers on hand.
> 
> Hi all,
> 
> Very happy to see progress being made here. Regarding 'styling' of the VTT 
> content, might I take this opportunity to point to this:
> 
> "[VP-2] The user can change the following characteristics of visually rendered 
> text content, overriding those specified by the author or user-agent defaults 
> (UAAG 2.0 1.4.1). (Note: this should include captions and any text rendered in 
> relation to media elements, so as to be able to magnify and simplify rendered 
> text):
> 
>    text scale (i.e., the general size of text),
>    font family, and
>    text color (i.e., foreground and background).
> 
> This should be achievable through UA configuration or even through something 
> like a greasemonkey script or user CSS which can override styles dynamically 
> in the browser."
> (source: Media Accessibility User Requirements - 
> http://www.w3.org/WAI/PF/media-a11y-reqs/#VP-2)
> 
>> From a practical perspective, it is significantly easier for third parties to 
> write scripts and/or user style-sheets if the content is all located in 
> one-place. For this reason, I would suggest that CSS be contained in a linked 
> style sheet, and *NOT* written in-line in the VTT file.
> 
> My $0.02 for what it's worth.
> 
> JF
> ------------------------------
> John Foliot
> Web Accessibility Specialist
> W3C Invited Expert - Accessibility
> Co-Founder, Open Web Camp
> 
> 
> 
> 
> 

David Singer
Manager, Software Standards, Apple Inc.

Received on Tuesday, 20 January 2015 15:17:19 UTC