When I create graphics for the web, I find that the lossless nature of PNG compression creates the best looking image files. Unfortunately, the trade off of having distortion-free images is a much larger file size than you’d have with nearly identical JPEGs.

However, in those cases where even a small amount of JPEG compression leaves distortions in my images, I opt for the lossless compression of PNG files, so that the images will look exactly the way I want them to. To offset the larger file size, I use an excellent (and free) command-line utility called PNGOut to reduce the PNG files another 10-15%.

Today, I wanted to see how PNGOut stacked up against its peers, so I exported one of my old Finetune Friday posters from Inkscape and ran it through three different PNG compression utilities. Even though I tried some of the more advanced options of the other utilities, PNGOut still provided twice the reduction of its closest competitor.

Orginal PNG File
218k

Lossless Compression
PNGCrush: 212k - 2.8% reduction
Optipng: 206k - 5.5% reduction
PNGOut: 195k - 10.6% reduction

Lossy Compression (For Comparison)
JPEG (no compression): 128k - 41.3% difference
JPEG (5% compression): 71k - 67.4% difference

PNGOut Download:

If you’re going to use PNG, I highly recommend using PNGOut.

Posted in Free Software