Re: Graphics formats

[Dave Pawson <davep@dpawson.co.uk>]

On Mon, 2005-04-18 at 09:49 +0200, Justus Piater wrote:

> 
> Here's what I think is the common wisdom:
> 
> 1. If your graphic data is in vector format:
> 
>    * Keep it in vector format for as long as possible during the
>      vector pipeline. I.e., never explicitly convert it to raster
>      format.
Yes. Good common sense. I fell in love with SVG the first time
I zoomed and it didn't pixelate!

> 
>    1.1. If you are targeting print output:
> 
>         Since you'll probably be generating PDF or PS, you'll
>         typically convert your graphics to (vector-format) PDF or EPS.
That's news to me. I've always favoured PNG. 

> 
>    1.2. If you are targeting Web output:
> 
>         The most common formats are SVG and Flash. I think the former
>         should be preferred as it is an open, non-proprietary XML
>         standard (and a W3C recommendation) for which many open and
>         non-proprietary processing tools exist.
> 
>         Since all vector-based Web graphics formats currently require
>         browser plugins (and in any case will continue to demand
>         sophisticated browsers), for maximum portability you will want
>         to offer an alternative raster image (inside an <object> tag,
>         for example). See 2.2.2 below for the recommended format.

Forget flash. Totally inaccessible. Once SVG is delivered as part of the
browser I'd be tempted. Untill then I know jpg is supported more than
widely.

> 
> 2. If your graphic data is in raster format:

Examples please? Typical extensions?
Put simply, what's your definition of raster format please?


> 
>    2.2. If you are targeting Web output:
<snip/>
  Thanks Justus. 

> 
> 
> The essence: Don't throw away any information if you can avoid it.
  Obvious, but your advice above tells us how, which is even more
useful :-)

> Note that PDF and PS/EPS can represent both raster and vector data.
Yes.... But PDF as an *image* format sounds just weird to me :-)
  perhaps I am just getting old.
> 
> There are open-source tools for essentially all conversions that arise
> in practice.
Oh but I do wish Irfanview were available to me under Linux.
   (off we go again)
What do you use please Justus?

>  The hardest are probably conversions to and from SVG.

How about screen capture, save as PNG?
 On windows I was more than happy with 'snag-it'.
  Haven't found one on linux yet.

regards DaveP