If you need to compress images for optimum use on the web, I recommend reading this article which I have had satisfactory results.
Based on the fact that you have no restrictions on installing anything on the server, there is a section called "Tools and parameter tuning", where the best compression tools exist for each image extension. >
Tools and parameter tuning
There is no one perfect image, tool, or set of optimization
parameters that apply to all images. For best results you will have to
pick the format and its settings depending on the contents of the
image, and its visual and other technical requirements.
- gifsicle - Create and optimize gif images - link
- jpegtran - Optimizes JPEG images - link
- optipng - Optimizes PNG (lossless) - link
- pngquant - Optimizes PNG (lossy) - link
Do not be afraid to experiment with parameters of each compressor. Dial
down the quality, see how it looks, then rinse, lather and repeat.
Once you've found a good set of settings, you can apply them to other
similar images on your site, but do not assume that all images must be
compressed with the same settings.
I hope to be happy