Freeware multi-platform image viewer: nomacs
nomacs image lounge (all lowercase? ) (Version: 0.3.2.5828 beta tested) is an open source image viewer for Windows, Linux, and Mac machines. It supports the most common image formats from jpg to gif (no animations however) and xmp to pgm and others including the raw format. It is capable of reading and displaying exif metadata. It offers faster than most thumbnail view of images in a folder and a player to view a folder ala a slideshow.
The program can also be viewed in full screen or various levels of transparency and in frameless mode where the image only is shown, floating over the background. The toggle between frameless and normal view is not exactly obvious but a quick search revealed it to be F10.
On the image editing side there is crop, resize and a ‘pseudo color function’ where one can play with hue, saturation and RGB color values using a slider.
nomacs also features a synchronization feature that will work on computers on the same network or LAN.
nomacs does indeed seem faster than most. It can be found in various Linux repositories and there is a Mac port as well. Its Windows version runs on Windows 2000, XP, Vista and 7 and is available in both portable and installer versions.