- From: Chris Lilley <chris@w3.org>
- Date: Thu, 20 Oct 2005 22:15:31 +0200
- To: Bjoern Hoehrmann <derhoermi@gmx.net>
- Cc: www-svg@w3.org, David Singer <singer@apple.com>
On Sunday, April 24, 2005, 7:27:43 PM, Bjoern wrote: BH> Dear Scalable Vector Graphics Working Group, BH> http://www.w3.org/TR/2005/WD-SVGMobile12-20050413/ is unclear about BH> proper syntax for the 'data:' URL scheme, While sympathetic to your concern regarding implementations as articulated below, lets take this one step at a time. SVGT1.2 says that the syntax is defined by RFC 2397, which is a normative reference: [RFC2397] 'The "data" URL scheme', L. Masinter, August 1998. Available at http://www.ietf.org/rfc/rfc2397.txt. That RFC says dataurl := "data:" [ mediatype ] [ ";base64" ] "," data mediatype := [ type "/" subtype ] *( ";" parameter ) data := *urlchar parameter := attribute "=" value and If <mediatype> is omitted, it defaults to text/plain;charset=US-ASCII. Thus, we believe that the specification is in fact crystal clear regarding the exact syntax. BH> many SVG tools fail to specify BH> a proper media type for the data Yes, they do. Please complain to the producers of such tools. BH> in which case the scheme defaults to BH> text/plain;charset=us-ascii which is hardly ever intended for resources BH> included in SVG documents. Agreed, although with a caveat - there is no Media Type for fonts, despite several attempts to create such a thing - ages ago by myself, and more recently by Dave Singer with http://www.ietf.org/internet-drafts/draft-singer-font-mime-00.txt except its now expired: http://www.ietf.org/internet-drafts/draft-singer-font-mime-01.txt I copied Dave Singer on this message. I suppose that even so, something like x-font/x-opentype or application/vnd.whoever.fonttype could be used. BH> http://www.w3.org/2004/10/RecsFigure.svg is BH> an example for this. That example is not in our specification. Please complain to the tool vendor (Adobe) and also to the IESG for not allowing a font/* top-level type. BH> Please change the draft such that it is very clear to authors and BH> authoring tool developers that this is not acceptable and that BH> conforming user agents must not assume any other media type in this BH> case. I checked and there are no examples of data: URIs in our spec with incorrect media types, and the specification is quite clear on the subject. We find that there is indeed something of a problem with font Media Types, but that problem is not on our specification and it is not clear what we can do about it. In sum, focusing here on the actual specification, we find that there is nothing to change in this regard. -- Chris Lilley mailto:chris@w3.org Chair, W3C SVG Working Group W3C Graphics Activity Lead Co-Chair, W3C Hypertext CG
Received on Thursday, 20 October 2005 20:16:16 UTC