Re: comments on draft-barth-mime-sniffing

On Fri, Jun 19, 2009 at 7:05 AM, David Singer <singer@apple.com> wrote:

>  At 16:32  +1200 18/06/09, Robert O'Callahan wrote:
>
> On Wed, Jun 17, 2009 at 7:15 PM, Maciej Stachowiak <mjs@apple.com> wrote:
>
> On Jun 16, 2009, at 11:12 PM, Adam Barth wrote:
>
> I think roc was specifically referring to content for the <video> tag.
> Because no such content currently exists, the legacy compatibility
> requirements are much less onerous than, say, for HTML.
>
>
> I think Dave's point was that if you support codecs and containers in
> <video> that are currently supported by widely used plugins, then you are
> more likely to face these legacy issues with broken MIME types when
> deploying <video>. Content authors might well expect that already published
> MP4 files which work in the QuickTime plugin or a Flash-based player, should
> continue to work if embedded via <video>.
>
>
>
> They may expect that, but breaking that expectation is less of a problem
> than breaking actual existing content.
>
>
> sorry, you've lost me.  breaking that expectation does break existing
> content;  and I can't see how doing content sniffing breaks more content
> than not.  can you explain?
>

Currently there is almost no existing content that uses the <video> element
to play media files that are being served with incorrect Content-Types.
(Please correct me if I'm wrong about this.) Therefore, not sniffing for
<video> should break almost no existing content.

Maciej suggests there is a significant amount of content using plugins
(Flash or Quicktime, I suppose) to play media files served with incorrect
Content-Types, and therefore authors will be surprised if they attempt to
use <video> to play those files and they don't work.

I say that "author surprise" is much less of a problem than "existing Web
pages stop working".

Rob
-- 
"He was pierced for our transgressions, he was crushed for our iniquities;
the punishment that brought us peace was upon him, and by his wounds we are
healed. We all, like sheep, have gone astray, each of us has turned to his
own way; and the LORD has laid on him the iniquity of us all." [Isaiah
53:5-6]