In the Episode 10 of MacBreak Weekly, Leo revealed that he resorts to Photoshop when he wants to resize an image on his Mac. A little overkill for a relatively simple task, most of us would agree. I used to do the same, until I started playing with Automator and discovered this neat little trick.

Automator is Apple’s utility for doing repetitive tasks. It’s actually a scripting programme, but it has a simpler learning curve because of its graphical user interface. Here’s a simple plugin I created in three steps that lets me resize images from a right-click context menu.

Step 1: Build the workflow

When you launch Automator, you’ll see three columns: Library, Action and an empty workspace where you will build your workflow. Under each library item you will find the associated actions. Build the workflow by dragging the following actions into the workspace:

Finder: Get Selected Finder Items Preview: Scale Images

An alert pops up warning you that you will lose your originals unless you add another action before Scale Images. Click Don’t Add.

Look under Options for Scale Images. Set your default image scale size (e.g. 480px). Make sure ‘Show Action When Run’ is checked.

Step 2: Save the workflow as a Finder plug-in

Click File » Save As Plug-in… »

Give your plugin a name, e.g. Resize images, and save it as a Finder plug-in.

Step 3: Right-click to resize

Now look for a picture (or a few pictures) and right-click (or Control-click) on it. A contextual menu will appear. Point at the Automator option and another menu will appear with your newly-created Resize images plug-in.

If you had followed the instructions above and checked the ‘Show Action When Run’ checkbox, Automator will ask you how wide you want your resized image to be. By default, that figure is the value you specified in Step 1.

Click Continue, and Automator will go about its business. You’ll get an alert in your menu bar announcing Workflow Complete and now, the image(s) has been resized.

Easy! Now you’ve got a powerful, quick way to resize your images quickly. And all it took was a two-action Automator workflow. If all you have is a iBook G4 like me, you’ll appreciate the time you save by not having to fire up Photoshop everytime you want to resize an image or two. Another benefit is that the resulting images will open in Preview by default. I just hate it when I double-click an image and Photoshop starts up because I had resized it in Photoshop earlier.

If you’re interested in learning more about Automator and what it can do, check out MacBreak, the TWIT network’s great Mac video podcast netcast for lots of great how-tos. Two other great resources are Apple’s Automator tutorial and Automator.us. Tutorials aside, the easiest way to learn Automator is to give it a whirl and try creating your own workflows. And when you do learn a new trick please let me know.