GridPlayer

GridPlayer is a video player built around showing more than one file at a time. Instead of a single clip filling a single window, it places several videos side by side within the same interface, which suits work where two or more recordings need to be watched in parallel: different takes of the same scene, a source clip next to its re-encode, or material captured by several cameras.

The record describes it as a Linux application, so no build for other operating systems is listed. It is published by vzhd1701 and distributed under GPL-3.0-or-later, so the source may be studied and modified under the terms of that licence.

Details beyond the multi-video layout, such as supported container formats, synchronisation between panes, or keyboard control, are not covered by the information available here and are best checked against the project's own documentation before relying on them.