It's easy to put together a batch process in Photoshop to resize all the images in a folder to a certain height or width. However, if some of the photos are portraits and some are landscapes, they end up at different sizes. This script determines which dimension is the longest one and resizes that dimension to the specified number of pixels (set by the user). Note that this hint requires Photoshop, obviously...
This is set to save the images as JPEGs -- if you want it to save them in some other format, just change the line Save as JPEG in live_folder to Save as TIFF..., Save as Photoshop format..., Save as Photoshop EPS..., etc. (See the AppleScript dictionary for Photoshop for a complete list of formats.)Mac OS X Hints
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