Image Compression fo generated images

a lot of places do have the solution on this.
But a subsequent solution to the “problem” must be accompanied by a complete recalculation of the existing image formats. This is because you can only influence the calculation basis for the upload process. Existing images are not changed by the snippet alone.

some of the plugins that handle the recalculation do have a solution for uploading process too. Because i’m not shure if the enfold existing snippet:

add_filter("avf_jpeg_quality", "avf_set_quality_mod", 9999, 1);
add_filter("avf_wp_editor_set_quality", "avf_set_quality_mod", 9999, 1);
function avf_set_quality_mod($quality) { $quality = 55; return $quality;}

has influence on other image formats ( only pixel based can be handled on general ) but i guess that the snippet above does not work with png files.

A nice little tool is from Shortpixel reSmush.it – see some info: https://shortpixel.com/
for me the free version is good enough.