A.I. Gigapixel - AI based image resizer
Caesium Image Compressor - Compress your pictures up to 90% without visible quality loss.
AI Img Enlarger - Enlarge Images Without Losing Quality Online
XnConvert - XnConvert is an easy image converter for graphic files, photos and images available on Windows...
waifu2x - Online/Offline tool to upscale images
DVDVideoSoft Image Convert and Resize - Free Image Convert and Resize is a compact yet powerful program for batch mode image processing.