FFmpeg - Open source multimedia suite for conversion, playback, profiling, and streaming.
4k Video Downloader - 4K Video Downloader is a software program that helps people download video files from sites such as Facebook, YouTube and Dailymotion.
HandBrake - HandBrake allows users to easily convert video files into a wide variety of different formats.
Video DownloadHelper - Browser extension to download videos from the Web
Adobe Media Encoder CC - Create optimized video for any screen size and resolution with Adobe Media Encoder. Available only in Adobe Creative Cloud.
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.