Plugin skips 640×480 images

We’ve done additional research

First, checked the page and got 8 unoptimized images
https://cl.ly/3f1V0m2s2G0g

Then tried downloading all the images from the page and compress them using TinyPng site
https://cl.ly/3V0P3o0w012R

After that we uploaded compressed images back to /uploads/ folder
And checked again
https://cl.ly/2O3H2a2z0Z3P

The images size slightly changed but still considered unoptimized.

Why ?

Hi iftemplar,

You seem to have the right settings for compressing the original images.
We’ve noticed before that Google often reports that already compressed images can be compressed even more.
Google seemed to compress images more aggressively which resulted in smaller images but often also a visually noticeable difference.
?
The compression engine tries to find the optimal compression the first time you compress.
It is possible to compress an image again, sometimes further decreasing the file size.
However, doing this usually degrades the quality of the image.
Some images may not degrade as much as others, but there will always be difference. Therefore we recommend only compressing the image once.

Please compare a local true original image with the full size “original” image on wordpress, and see if the file size has changed.
If the file size has been reduced they are in fact compressed, just not as aggressively as google suggests.
If the file size has stayed the same please let us know so we can look further into this.