like pobocks says, imagemagick is an alternative. it's a very nice alternative if you ever need to do more, e.g. composite images, many more formats, add text/borders/effects. good fun, and quick.
the hardest line to type correctly is: stty erase ^H

In reply to Re^2: Resizing images with transparent background? by aquarium
in thread Resizing images with transparent background? by Anonymous Monk

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