0Testing new image compression tools

I’ve been using EWWW image optim­iser to com­press all of my JPEG and PNG images on this site for sev­er­al years. EWWW makes use of OptiPng and PngOut and whilst these are power­ful tools there are altern­at­ives out there now that I wanted to test and compare.

I am aware of new­er image formats that may offer smal­ler sizes but until they are broadly sup­por­ted we will have to con­tin­ue to work with PNG and JPEG.

I have already seen some com­par­is­ons show­ing some impress­ive per­form­ance by some oth­er formats but I wanted to test this for myself with my real­world images. Based on the claims presen­ted I decided to start with Pingo and see how much it reduced the size of my total image library.

There are 3549 images which are a mix of PNGs, JPEGs, and Webp files and range in size from over 1000×1000 pixels to small thumb­nails of 60×60 pixels.

Lossless

3505 images were pro­cessed in 434 seconds which is impress­ively quick com­pared to the pre­vi­ous tools I’ve used. How­ever, only 3455kb (3.37mb) was saved which is a 2.5% saving.

Des­pite the lack of reduc­tion, I will still be look­ing to migrate to pingo as it is vastly faster than the tools used by EWWW and achieves effect­ively the same result

Lossy

Lossy com­pres­sion was much more impress­ive in size reduc­tion with a 22.6Mb (19%) reduc­tion but this is to be expec­ted as my pre­vi­ous tools were not using lossy com­pres­sion. I had decided in advance that a sig­ni­fic­ant reduc­tion would be needed for me to con­sider using lossy com­pres­sion. This reduc­tion is right on the bor­der­line. The ulti­mate decision comes down to how much the smal­ler dimen­sion (more often served) images saved — the major­ity of the sav­ings were with ori­gin­al images not with the smal­ler images so I’m not per­suaded that the reduc­tion is worth­while at this point, espe­cially as I already serve webp images to over 50% of vis­it­ors and these gained the least

The next step is to fig­ure out how to auto­mate the pro­cess with pingo which isn’t sup­por­ted by EWWW.