Optimizing images is the easiest way to boost speed and search ranking. Start...

https://wiki-cable.win/index.php/Beyond_the_Alt_Tag:_Why_Your_Schema_Needs_High-Quality_Image_Optimization

Optimizing images is the easiest way to boost speed and search ranking. Start by naming files descriptively—ditch the generic "IMG_001"—and write alt text that actually describes the content