image compression: how does webpagetest check if an image can be compressed??!?

hey! I was wondering how exactly webpagetest figures out if an image could be more compressed or not, so I could test/tweak stuff see if my site is generating the “right” sized images

i gave a shot at looking at the source and found this constant in which looks like maybe a clue… →
37:static const BYTE JPEG_DEFAULT_QUALITY = 30;


bump bump

The code you’re looking for is actually here:

It recompresses jpegs at a quality level of 85 which is pretty generous (usually you can go down to 75 without even thinking about it). The process also strips out meta-data like exif tags.

cool! thanks Pat! :smiley: :slight_smile: :wink: :angel: