The MIDI support for the OS/2 multimedia system handles the RIFF RMID data type, as well as standard MIDI file formats 0 and 1. MIDI file format 0 merges tracks of MIDI data into one track; MIDI file format 1 preserves the separate tracks of data. MIDI file format 2 is not supported.
MIDI files are made up of chunks, similar to RIFF chunks. In MIDI files, there are two types of chunks: header chunks and track chunks. A header chunk provides a minimal amount of information pertaining to the entire file. A track chunk contains a sequential stream of MIDI data, which can contain information for up to 16 MIDI channels.