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Re: do vector graphics enhance our concept of self?

From: jonathan chetwynd <j.chetwynd@btinternet.com>
Date: Mon, 29 Jul 2002 21:18:08 +0100
Message-ID: <008501c2373d$15eb7380$0201a8c0@RJCHETWYND>
To: "Charles McCathieNevile" <charles@w3.org>
Cc: "Danny Ayers" <danny666@virgilio.it>, "Jon Hanna" <jon@spin.ie>, "WAI List \(E-mail\)" <w3c-wai-ig@w3.org>

chaals,

the problem staring us in the face, is that jpegs dont scale, like vectors.
there are some vector faces here:
http://www.eboy.com/pages/works/vectors/vectors_09.html
they have a large file size(30K), and whilst probably recognisable are
certainly not photographic.

Can anyone point to realistic vector portraits, with a small file size?

jonathan



----- Original Message -----
From: "Charles McCathieNevile" <charles@w3.org>
To: "jonathan chetwynd" <j.chetwynd@btinternet.com>
Cc: "Danny Ayers" <danny666@virgilio.it>; "Jon Hanna" <jon@spin.ie>; "WAI
List (E-mail)" <w3c-wai-ig@w3.org>
Sent: Monday, July 29, 2002 1:27 PM
Subject: Re: do vector graphics enhance our concept of self?


>
> I think the situation is a bit more complex than you seem to suggest.
>
> There are technical reasons why jpeg doesn't have transparency, although
it
> does have good compression for photograph type images. GIF and PNG, on the
> other hand, have transparency, but very poor compression for photographs
(by
> comparison). Essentially using these types of technology you have to make
a
> trade-off - you get one or the other.
>
> In some cases SVG should be used to replace PNG, JPEG or GIF images
> (perhaps most cases where png or gif are a good choice SVG is a better
> technical choice, and as user agents and authoring tools become more
common
> will be a better overall choice).
>
> In other cases SVG allows you to combine the best features of SVG with the
> best features of JPEG (its compression for certain types of image) or
PNG/GIF
> (Hmmm. The more I think about it the more I wonder what you really gain by
> keeping those formats. I am sure there are relevant cases though).
>
> I am not familiar with all the SVG authoring tools. However, to create a
tool
> which allows you to trace a section of a jpeg and say "show me just that
> section" isn't hard. Jim Ley has such a tool available, in an online
version
> written in SVG. (He uses it for providing more useful searchable
information
> about the bit of the image that you trace, but it can also provide a
clipped
> region).
>
> This thing can be animated or scripted to move around, and again Jim has
> demos. (Because these are things he works on for a bit of fun, the script
> changes from time to time. But I believe that he is happy for people to
use
> it).
>
> It is possible to use this to create a complete user interface, but it
takes
> some programming time - generally available at the whim of a programmer or
by
> paying for it.
>
>
> Technically, following the approach Jim has taken is the best method I can
> think of. In terms of getting a tool that makes it easy, it also seems the
> best approach I can think of. If you want something that a person with
> relatively basic programming skills can work on, it is perhaps also the
best
> option. I you want me to program it for you then all you need to do is
find
> me the time ;-)
>
> Seriously, I appreciate that you want better tools. Me too. And world
peace.
> I think the best approach is to follow the mixed SVG/JPEG method,
especially
> if you want to do animation.
>
> Cheers
>
> Chaals
>
> On Sat, 27 Jul 2002, jonathan chetwynd wrote:
>
> >
> >Yes Chaals,
> >but the unfortunate fact is that with a gif one can just choose a 'magic
> >wand tool' and the job is kind of done.
> >whereas for svg, one remains in a kind of fantasy land, ie highly work
> >intensive, and only partially meeting the needs*.
> >
> >Jon,
> >as far as png files go, as far as my limited (ie one file) test showed
there
> >was a 5-10% compression saving on gif, hardly comparable with ~300% for
> >jpeg.
> >
> >Surely it must be plain that with all the open source productivity
available
> >a concerted effort to either get the jpeg source released, reverse
engineer,
> >or create a new source is a reasonable project?
> >SVG is not intended to replace jpeg or gif as I understand it, or did I
get
> >this wrong to?
> >
> >thanks again
> >
> >Jonathan
> >
> >On degredation, transparency is lost, so all the tracing goes to waste.
> >Transparency is fairly fundamental to sprites.
> >Its this degredation, that is the concern, or more significantly, the
> >attitude to it, for meta-freaks.
> >
> >----- Original Message -----
> >From: "Danny Ayers" <danny666@virgilio.it>
> >To: "Charles McCathieNevile" <charles@w3.org>; "Jon Hanna" <jon@spin.ie>
> >Cc: "WAI List (E-mail)" <w3c-wai-ig@w3.org>
> >Sent: Friday, July 26, 2002 7:27 PM
> >Subject: RE: do vector graphics enhance our concept of self?
> >
> >
> >>
> >> <clippath d="[[here you need a path around the bit of the image that
> >> >you want - this can be generated quickly by tracing out the image,
> >>
> >> Amaya's good for that...
> >>
> >>
> >
> >
>
> --
> Charles McCathieNevile    http://www.w3.org/People/Charles  phone: +61 409
134 136
> W3C Web Accessibility Initiative     http://www.w3.org/WAI  fax: +33 4 92
38 78 22
> Location: 21 Mitchell street FOOTSCRAY Vic 3011, Australia
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>
Received on Monday, 29 July 2002 16:18:58 GMT

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