Shrinking a lot of jpegs?

[Bruce Smith <bruce@xxxxxxxxxxx>]

I'm looking for a program that can shrink a large amount of
jpeg's by a certain percentage, without manual intervention.

I have a lot of pictures taken with my digital camera that
I would like to put on a web page.  The pictures are large
and there are a lot of them.  To many MB for one web page.
I'd like to create the web page so there are small pictures 
people can click on to see the large one.  (thumbnails?)

I realize that programs like "xv" and "gimp" can do this,
but I only know how to do it manually.  Loading each picture,
shrinking it, and saving it under a new name.  This is very
time consuming for a large number of pictures.  I want to 
just give a directory or file list to a program, press ENTER
and have it do them all without any more work.

Is there a *Linux* program that can do this?

I've read something about gimp doing some scripts.
Is that a possibility?  I'll read up on gimp if that is a
good answer, but I don't want to go chasing my tail with
gimp if it's not able to do this.

For an example of a page where I made the thumbnails manually, 
go to:  http://kalamazoolinux.org/~bruce/wildlife.html
and click on "Hummingbirds".  That's only 30 pictures.
I have 116 pictures of the Tall Ships leaving South Haven . . .

BTW, for PHP users, the hummingbird page is a PHP script that I
supply a couple parameters to, like the number of pictures, and
it creates the entire web page automatically.  I can post a copy
to the phpsig list if anyone is interested. 

--------------------------------------------
Bruce Smith                bruce@armintl.com
System Administrator / Network Administrator
Armstrong International, Inc.
Three Rivers, Michigan  49093  USA
http://www.armstrong-intl.com/
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