Radical Image Optimization Tool (RIOT) is a free image optimizer that will let you visually adjust compression parameters while keeping minimum file size.

Reduce Image Size
RIOT will reduce image size. It uses a side-by-side or single view interface to compare the original with the optimized image in real time and instantly see the resulting file size.
It is lightweight, fast and simple to use, yet powerful for advanced users. You will be able to control compression, number of colors, metadata settings and much more, and select image format eg JPG, GIF or PNG, for your output file.
Available as stand-alone executable or dynamic link library for developers, RIOT can also be used as plugin for programs like The GIMP, IrfanView or XnView.
Home page: Radical Image Optimization Tool.
FILEminimizer Pictures is another free software to reduce the size of your images, photos and pictures.
Speaking of optimization … have you optimized your Windows 7 folders, for a fast load up? If not, check this tip!
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