Demultiplexer (media file)

A demultiplexer for digital media files, or media demultiplexer also called a file splitter by laymen or consumer software providers, is software that demultiplexes individual elementary streams of a media file, e.g., audio, video, or subtitles and sends them to their respective decoders for actual decoding. Media demultiplexers are not decoders themselves, but are format container handlers that separate program streams from a file and supply them to their respective audio, video, or subtitles decoders.

Playback difficulties (such as no playback, no audio, or no video) may result from several or legacy file splitters for a particular file format being installed on an operating system. This causes decoder-to-file-splitter mismatch resulting in playback failure on media players.

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