We have observed the image compression for PNG in WCH during image rendition is not optimal. When compared with TinyPNG we see huge difference.
The original image was 1.1mb
When I ran it through TinyPNG it get's compressed to 260KB
When I ran it through WCH compression it get's compressed to 729kb
There are no obvious visual differences between the image compressed but better compression helps with rendering performance specifically with mobile devices with smaller files to download.