XnView is a multi-platform software used for viewing, converting and manipulating graphic files. It supports more than 400 image file formats, is free of charge for private usage, easy to use and requires no installation (portable software).
Features:
* Import about 400 graphic file formats
* Export about 50 graphic file formats
* Multipage TIFF, Animated GIF, Animated ICO support
* Image IPTC, EXIF metadata support
* EXIF auto rotation support
* IPTC editing
* Resize, rotate, crop support
* Lossless rotate & crop (jpeg) support
* Adjust brightness, contrast...
* Auto levels, contrast
* Modify number of colors
* Apply filters (blur, average, emboss, ...)
* Apply effects (lens, wave, ...)
* Fullscreen mode
* Slide show with effects
* and more...