I have a mystery over here.
For some reason, a WordPress site is generating really low quality thumbnails. They look like a JPG with quality 20 or a GIF file with only a couple of colors with some dithering.
I’ve tested the original images and there’s nothing wrong with them since their thumbs on a different WordPress site look good.
It’s also no CSS or anything since when i save the generated thumb the low quality is in the image itself.
I’ve searched the internet and found some threads but none with a clear answer and some which where caused by some weird CSS rule.
What could be the problem here?
If i remember there is filter for quality of thumbnails, check this post here: http://wordpress.org/support/topic/setting-jpeg_quality
Start there, maybe somewhere in plugin or theme someone mess with it.
Allready tried that. The site has nog weird plugins or whatever.
Could it be a server/php related thing?