John,

I have a first working version of an interface to the 
LIBJPG standard reference library. I's written in ANSI C, 
and what I did is a small squeak plugin that is linked with 
libjpg to build the dll. It can read and write jpeg images 
and is really fast. It's nos exactly what you want, but its 
a lot easier to do and to mantain, because libjpg will be 
kept updated. It's still not finished, that's why I haven't 
published it. It should be part of PhotoSqueak, together 
with a similar interface to libtiff.
I can send it to you later today, when I get back home.

Regards,
Juan Manuel Vuletich
http://www.sinectis.com.ar/u/jmvuletich/studio.html

>  Bob,
>  
>  Many thanks, but I actually already have a solution that 
works on Windows.
>  It uses a very fast (and free!) library from Intel. But, 
it only works on Pentium
>  and StrongARM processors. I was looking for a truely 
cross-platform solution,
>  ideally implemented in Squeak itself with primitives 
that can be generated
>  via the ST-to-C translation, like the current JPEG 
reader. Such a solution would
>  work on *all* Squeak platforms.
>  
>  Thanks for the offer, though.
>  
>  	-- John
>  
>  
>  >John,
>  >
>  >I have a cheesy JPEGReadWriter 
class>>putForm:onFileNamed: method that
>  >writes a BMP file, then uses FFI to launch a batch file 
that executes CJPEG
>  >to convert it.  It works nicely, but only for Windows, 
and it's far from
>  >elegant.  Let me know if you want it.
>  >
>  >	-Bob
>  
>  
>  
>