FIS3 picture compression size unchanged?

  node.js, question

How does fis3 compress the picture?
First of all, the fis-optimizer-png-compressor plug-in built into the official website does not compress the current picture size.
Secondly, no other image compression plug-ins about fis were found in the plug-in library.
Some children’s shoes are using fis and know how to deal with image size compression correctly. Thank you!

It is effective. Before compression图片描述

After compression:图片描述

You can see that both a.png and b.png are getting smaller.
My fis Configuration:

fis.match('*.{js,css,jpg,png}', {

This method can reduce the size of the picture by about 10%. Also, from the name of the plug-in, it can be seen that the plug-in only has effect on png pictures.