Is it possible to scan an image from the command line?

Is there a tool that scans images from the command line? I am looking like scanimage on linux that works like this:

scanimage > image.pnm

I've tried googling and checked if ImageCapture is scriptable via applescript but no results.

I don't know of a way to do it with built in tools, but there is an OS X version of SANE that should be able to do exactly what you request (scanimage > image.pnm).

SANE

This is a TWAIN datasource for MacOS X that aquires images using the SANE backend libraries. The SANE backend libraries provide access to a large range of scanners connected through SCSI or USB. For a complete list see the documentation on the SANE project homepage.

It's available at http://www.ellert.se/twain-sane/

You might also be interested in scanline, which does what you're requesting:

http://blog.scottkleper.com/scanline-command-line-scanner-for-mac/

(Disclaimer: I wrote scanline. It's free and open source)