[Webkit-unassigned] [Bug 47512] Add support for decoding WebP image

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=47512





--- Comment #15 from Adam Barth <abarth at webkit.org>  2010-10-12 23:08:30 PST ---
... with my "spec lawyer" hat on:

http://www.whatwg.org/specs/web-apps/current-work/#the-img-element

"The user agents should apply the image sniffing rules to determine the type of the image, with the image's associated Content-Type headers giving the official type."

which refers to http://www.whatwg.org/specs/web-apps/current-work/#content-type-sniffing:-image

"The rules for sniffing images specifically and the rules for distingushing if a resource is text or binary are also defined in the Media Type Sniffing specification. Both sets of rules return a MIME type as their result. [MIMESNIFF]"

which refers to http://tools.ietf.org/html/draft-abarth-mime-sniff-05#section-6

so, at least from HTML5's point of view, the behavior of this code in specified by draft-abarth-mime-sniff.  Now, that document says:

   "User agents MAY support additional types if necessary, by implicitly
   adding to the above table."

which is what we're doing in this patch.  However, at some point, presuming WebP becomes popular, we'll want to add the WebP signature to that table.  We'll save ourselves a lot of pain later if we all use the same high-quality signature from the beginning.

I've been talking with Pascal directly about what might be a good signature to use.  Apparently, we can use RIFF????WEBPVP8\0x20 currently, which is probably ok.  I've asked whether we can tweak the format to be RIFF????WEBPVP8\0 (replacing the last space character with a null byte), which would be an improvement from a sniffing perspective.

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.