Imagine you've just returned from vacation and are sitting down to look at pictures from your trip. For anyone who enjoys photography, this can be a daunting task as you find yourself sifting through hundreds, or even thousands, of photos. However, this time-consuming process can go much faster if you use an image viewer rather than RAW developers or database-driven photo collectors, such as Darktable or Lightroom. What you want is an image viewer that can quickly load even high-resolution RAW images from full-frame DSLRs and that can also handle larger image collections.

In the open source universe centered around GNU/Linux, there are numerous candidates for this task, from simple image viewers without further functions up to genuine all-rounders with numerous image processing functions. In this overview, we focus on image viewers in the narrower sense, excluding RAW developers with image databases for managing photos such as Darktable or RawTherapee.

Requirements

An image viewer has one primary task: It has to display images on the screen. It should also be capable of handling exotic formats and loading the pictures at lightning speed. The output of Exif information – such as exposure time, aperture, and focal length – or a map with the position of the shot helps to classify the images.

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