DigiKam is an open-source photo management application that runs on Linux, Windows, and MacOS platforms and comes with tools for importing, managing, editing, and sharing photos and raw files. The last version 6.0.0 has now video support and new export tools.
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The open-source core of Pinry, a tiling image board system for people who want to save, tag, and share images, videos and webpages in an easy to skim through format.