Codecs
K-Lite Codec Pack Mega
When a video file has no sound or a media player cannot recognize its format, K-Lite Codec Pack Mega adds codecs and filters for playback in Windows applications
K-Lite Codec Pack Standard
People who use Windows media players may run into files that lack the filters needed for audio or video playback
K-Lite Codec Pack Full
Video or audio files that won’t play in your Windows media player
MPEG-2 Video Extension
MPEG-1 and MPEG-2 videos can play in compatible Windows apps, and supported files can show thumbnails in File Explorer
MediaInfo
Need to know which codec, bitrate or resolution a video file really uses
AV1 Video Extension
When a video encoded in AV1 will not play in a Windows media app, AV1 Video Extension adds codec support for compatible apps
FFmpeg
Need to convert, trim or re-mux audio and video files from the command line