Mirage!

nomacs is a free image viewer for windows, linux, and mac systems, which is licensed under the GNU Public License v3. nomacs is small, fast and able to handle the most common image formats including RAW images. Additionally it is possible to synchronize multiple viewers. A synchronization of viewers running on the same computer or via LAN is possible. It allows to compare images and spot the differences (e.g. schemes of architects to show the progress).

JPEGView is a small and fast viewer/editor for JPEG, BMP, PNG, GIF and TIFF images. On-the-fly image processing is provided - allowing to adjust typical parameters as sharpness, color balance, contrast and local under-/overexposure.

Geeqie is a lightweight Gtk+ based image viewer for Unix like operating systems. It was forked from GQview. The development is focused on features for photo collection maintenance: raw format, Exif/IPTC/XMP metadata and integration with programs like UFraw, ImageMagick, Gimp, gPhoto or ExifTool.

Its minimalistic interface provides more screenspace for your images. Among its features are:

PhotoQt is a simple, yet powerful and good looking image viewer, written in Qt, published as open-source, and completely free.Photo comes with a variety of features. Most features you would expect from a image viewer should be there.All features of PhotoQt are very easy to use. Should you happen to be confused about some feature, have a look at the settings. Pretty much everything can be adjusted in PhotoQt, and every setting comes with a short explanatory text.

Phatch = Photo & Batch! Phatch is a simple to use cross-platform GUI Photo Batch Processor which handles all popular image formats and can duplicate (sub)folder hierarchies. Phatch can batch resize, rotate, rename, ... and more in minutes instead of hours or days if you do it manually. Phatch will also support a console version in the future to batch photos on web servers.

Free Opener allows users to view, edit and print many different types of files without having to download specialty software. Currently, the software supports over 80 different file formats including Microsoft Office Files (.doc, .docx, .ppt, .pptx, .xls, .xlsx, .xlsm, .msg, .vcf), Adobe Files (.swf, .flv, .psd, .pdf), Media files (.avi, .flv, .mid, .mkv, .mp3, .mp4, .mpeg, .mpg, .mov, .wav, .wmv, .3gp, .flac) and many others.

Universal Viewer is an advanced file viewer for wide range of formats. Supported file formats are:

Simplistic Image Viewer with focus on speed of rendering and switching between images. A good complement when no editing capabilities are nessesary.

QuickViewer is a graphic image viewer for comfortable browsing of many images.

You can use the Photos app to view or edit photos and videos in your Pictures library and on OneDrive, and to import photos and videos. The Photos app includes a wide range of editing options to enhance your photos, from automatic fixes to advanced adjustments. After you've finished editing your photos and videos, you can then share them with friends and family without leaving the app.