How to batch create SD images from HD in 1,2,3 steps :)

With iPhone 4 and all, now we need two sets of art assets, one for SD and one for HD (for retina display). So my artist gives me the assets in HD, and I:

1. Make a copy of the assets.
2. Use A Better Finder Rename 8 to rename the copied assets’ file names (append the suffix @2x or -hd).
3. Select all the original assets, right click, and open it in Preview. Once in Preview make sure all the assets are selected and then click Tools > Adjust Size (oh, the sizes of the assets should be uniform), and then you change then width and height to SD. And then Save All. (Source: http://www.usingmac.com/2008/6/10/batch-resize-images)
4. And then, what step 4? We are done 🙂

EDIT:

Or, if you happen to be using Cocos2D, you can use TexturePacker, to create a SD spritesheet from a HD spritesheet, with only 1 click!

Open your TexturePacker file with HD images (texture and data file name should end with @2x or -hd), and then click on AutoSD,

and when you publish, you will automatically have an SD version.

There we go, only one step 🙂