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Revision as of 05:57, 2 August 2020 by Trev (talk | contribs) (Midi file format: Add details and link to MIDI spec)

MIDI file format

Standard MIDI Files (SMF) contain all the MIDI instructions to generate notes, control individuals volumes, select instrument sounds, and even control reverb and other effects. The files are typically created by a "MIDI sequencer" (software or hardware) and then played on some kind of MIDI synthesizer.

Unlike digital audio files (.wav, .aiff, etc.) or even compact discs, a MIDI file does not need to capture and store actual sounds. Instead, the MIDI file can be just a list of events which describe the specific steps that a soundcard or other playback device must take to generate certain sounds. This way, MIDI files are very much smaller than digital audio files, and the events are also editable, allowing the music to be rearranged, edited, even composed interactively, if desired.

The format also allows tagging the file and the data in the file with copyright notices and other text "meta-events".

All popular computing platforms can play MIDI files (*.mid) and there are thousands of web sites offering files for sale or even for free. Anyone can make and share a MIDI file, using software that is readily available on smart phones, tablets and computers.

The Standard MIDI File Specification is included in the Complete MIDI 1.0 Detailed Specification document (1996). A number of changes/additions became part of the MIDI 1.0 Specification after the "96.1" publication and should be consulted to have a current understanding of MIDI technology.

Playing MIDI

Standard MIDI Files (SMF) contain sound events that indicate the notes and instruments in a musical performance, but do not include the digital waveform of the audio. They usually have the extension .mid or .midi. To play a MIDI file, software has to synthesize the music, which usually requires reading digital samples of musical instruments from a large file.




  • macOS MIDI Player Example code for a minimal application to play MIDI and iMelody files.

External links

See also