MKV is a container format for holding multiple audio, video, picture, and text data such as subtitle tracks. It is similar to other common containers like MP4 and AVI, although MKV is open in the specification. For video contents, MKV uses a .mkv filename extension, .mka for audios, and .mks for subtitles.
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Although not a format itself, Facebook has some technical requirements regarding the type of audio/video format it supports. While most file formats are supported, it’s best to use either MP4 or MOV. Also, the video compression codec should be in H.264 with AAC sound compression at 128kbps+. You can convert any video file type to Facebook using programs such as Wondershare UniConverter, VLC Media Player, Aiseesoft Video Converter Ultimate, and more.
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