Unix commandline utilities for modifying images

[Rodney Tamblyn]

Does anyone know of any Unix command line utilities for 
converting/adjusting images?  The type of things I'm imagining are 
scaling, rotating and saving (probably to jpeg, if I could specify 
parameters such as quality, so much the better).  If anyone has 
examples showing usage that would be a help.  I'm running OSX 10.1.5 
The alternative is to use Applescript and a freely available 
application like Graphics Converter (which I know will work).

Rodney

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Rodney Tamblyn
401 North 6th Ave,
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