Free Duplicate Finder use the source code of Video Duplicate Finder under license GPLv3 .
The Video Duplicate Finder official website: https://github.com/0x90d/videoduplicatefinder/

Free Duplicate Finder is a cross-platform software to find duplicated video (and image) files on hard disk based on similarity. That means unlike other duplicate finders this one does also finds duplicates which have a different resolution, frame rate and even watermarked.
Note: doesn’t support 32bit machine

Features

• Cross-platform
• Fast scanning speed
• Ultra fast rescan
• Finds duplicate videos / images based on similarity
• Windows GUI, Linux GUI and multi-OS Console