- From: lilley <lilley@afs.mcc.ac.uk>
- Date: Mon, 5 Feb 1996 15:11:46 +0000 (GMT)
- To: masinter@parc.xerox.com (Larry Masinter)
- Cc: wpk@fc.net, www-talk@w3.org
Larry Masinter writes: > William King wrote: > > > Is it not true that as long as folks ignore the central issue of > > standardization of content and the provision of conformance testing tools > > and branding programs for clients and servers, then they're going to get > > bogged down trying to solve peripheral and unnecessarily complex problems > > such as this one? Yes, that seems a fair summary. > > However, focusing more resources on the conformance and branding problem > > might just cause of lot of this other stuff to go away. A lot, yes. There have also been proposaly to make processing of marked sections a requirement for HTML UAs which would cause even more of the problems to go away. > The problems of content type negotiation with versions, features, and > the like is something that has been an issue for as long as there have > been computers, and doesn't seem to go away no matter what the forum. Yes, although negotiating on actual features rather than bugwards compatibility or 'browser x puts 6 blank pixels here while browser y only puts 4' sure cuts down the problem a lot as William notes. > If you have a "Microsoft Word" file, you actually have to identify, in > some situations, whether you have Word for Windows, Word for WIndows > for Workgroups, Word for Macintosh, version 5,6, 7, etc. These are all > the same brand, and they have some amount of interoperability. Hmm - yet these are all application/x-ms-word > If you have a "TIFF" file, you need to know, in some circumstances, > whether it is TIFF class B, class F, or uses non-standard tags. Indeed. Although if you read the registration document, all image/tiff files are supposed to be black-and-white class F files ;-) > Over time, some of the complexity in document formats goes away. Some > of the enhancements get dropped, everyone finds a least common > denominator to support, differentiation beyond that becomes > unimportant, and stuff converges. Which reduces the problem, but does not eliminate it. > There's a lot fewer image formats > floating around now than there were 3 years ago, for example. Depends on your sample. We have converters installed for around 200 formats here, for example. But yes, the lack of working content negotiation has seen the Web settle on GIF and JFIF pretty quickly ;-) > (I'm surprised at the rise of PNG though.) Given what you say about TIFF, and also given that TIFF and GIF are patent compromised, the rise of PNG should hardly be a surprise. Note also that PNG takes care to differentiate between core chunks, public extension chunks, and private chunks and has explicit rules to ensure PNG files can be exchanged in a robust manner. Thereby eliminating many of the content negotiation parameters that would be requird to exchange, say, TIFF files reliably. > So, I don't think that the issue of feature sets, characteristics, > etc. for media types is going to go away, as long as there are new > encapsulations of intellectual content ("document formats") to be > invented. Right. A pity, then, that MIME types are still so email centric and not really all that suited for the sort of fine grained negotiation that still seems to be needed even after the bugwards compatibility issues are removed. -- Chris Lilley, Technical Author and JISC representative to W3C +-------------------------------------------------------------------+ | Manchester and North Training & Education Centre ( MAN T&EC ) | +-------------------------------------------------------------------+ | Computer Graphics Unit, Email: Chris.Lilley@mcc.ac.uk | | Manchester Computing Centre, Voice: +44 161 275 6045 | | Oxford Road, Manchester, UK. Fax: +44 161 275 6040 | | M13 9PL BioMOO: ChrisL | | Timezone: UTC URI: http://info.mcc.ac.uk/CGU/staff/lilley/ | +-------------------------------------------------------------------+
Received on Monday, 5 February 1996 10:14:13 UTC