you can specify your optimization level for JPG compression. To do so, just set quality value by slider with a value between 25 and 100. For having a good image quality, please remain above 90. And default value is 92.
EXIF data are remove by default, reducing file size. However, these data can be keeped while compression by keep EXIF data checkbox.
It limits its use to PNG, JPG, GIF, BMP and TIF pictures up to 5MB.
it provides a FREE optimization of pictures, for the most standard filetypes (PNG, JPG, GIF, BMP and TIF). It allows reductions until 80% by using differents algorithms :
Original picture (left/first) 482,6 Kb, Optimized picture (right/second) 153,1 Kb : gain 68%
Original picture (left/first) 262,1 Kb, Optimized picture (right/second) 154,1 Kb : gain 41%