There are many graphics and photo editing programs for the Mac that can resize images, but few make the process as painless as ImageXY. This handy utility that does one thing, resize images to preset sizes, but does it quickly and easily.
To use ImageXY (pronounced image ex-see), first you drag one or more JPEG, GIF, PNG or PSD images into the program's window, which then displays a grid of thumbnails for those images. I wish the program indicated the number of images as well, when you're resizing a large batch of images, this would be useful.
Next you choose the target size from the Resize To popup menu. ImageXY includes five presets: Email (800 pixels wide), Web (480 pixels wide), Avatar (128 by 128 pixels), Blog (640 pixels wide) and Half (50 percent of the original size).
You can also create your own presets: Just choose Create Preset, give the preset a name, and then enter the target size. To resize to particular dimensions, just type the number of pixels for the target height, width or both. To resize to a specific percentage of the current dimensions, type the target percentage followed by % (for example, 45%).
Click Resize and ImageXY goes to work. The process of resizing images is pretty quick: On a 1.4GHz 2010 MacBook Air, it took approximately 25 seconds to resize 101 images. On a 2.7GHz 2010 iMac, the same task took just seven seconds.
Your original images are left in place, untouched. ImageXY saves the resulting resized images in ~/Library/Photos/ImageXY.
If one of your target dimensions is larger than that of an image you're resizing, or if your target dimensions have a different proportion than an original image, ImageXY helpfully pads the resulting image with black space. This is a nice touch, but I wish the program offered an option to choose the colour or transparency for that fill space. There are also times you may want to not pad the resulting image.
You can also drag images directly from iPhoto into the ImageXY window, and you can drag entire folders or volumes, such as a digital camera's media card, into ImageXY. The program will find all images in that folder or volume and resize them en masse. Unfortunately, the resized versions are dumped unceremoniously at the root level of ~/Pictures/ImageXY, rather than in folders that reflect the organisational hierarchy of the originals.
If you need to edit or process your images, you'll want a full featured image editor such as Acorn or Photoshop. But for frequent resizing tasks, ImageXY is quick to launch, easy to use and fast to finish.