Images on the web can be a brilliant UX enhancement. Or they can be a serious impediment to users trying to load your pages. Don’t frustrate your users with gigantic image files. With just a couple of small, free apps for your Mac, you can process images before adding them to a theme or uploading them to your site as content.
(Sorry, PC users. We like you, we just don’t own any PCs.)
JPEGMini Lite dubs itself a “diet for your photos” for good reason. It can reduce your jpgs by half or more. The best part is it only takes a few seconds. Open up the app, drag in a jpg and wah-lah! Your image is compressed and optimized. I love watching the file sizes go down as I run jpgs through the app.
What JPEGmini is to jpgs, ImageAlpha is to png files. ImageAlpha reduces png file sizes "by applying lossy compression and conversion to a more efficient PNG8+alpha format.” Drag a png file into the editing area, optionally adjust the sliding colors bar and click File > Save As. Before saving, check the “Optimize with ImageOptim” box to open the companion app (see the next app below).
Note: The site says version 1.3.5 is for Mac OS X 10.7-10.9, but I’m running it on OS 10.10.3 with no problems.
ImageOptim compresses image files and can be used alone or in conjunction with ImageAlpha. It does a wonderful job of squeezing the junk out of pngs. The decreased file size results in no lose of quality as far as I can see. (I’ve even run JPEGmini Lite-optimized jpgs through it, and occasionally it will take off a few bytes.)