MIDI to SP-MIDI Transcoding Using Phrase Stealing

The Musical Instrument Digital Interface (MIDI) is a popular music format used in mu ltimedia messaging service, such as mobile phone ringtones. Scalable Polyphony MIDI (SP-MIDI) is an enhanced format that allows composers to specify how MIDI data should be performed by hardware devices with different numbers of polyphonic voices. Most current mobile phones only support SP-MIDI ringtones with specific polyphonic limits. Since most MIDI files are composed without regard to polyphonic limits, a common problem in the mobile phone industry is conversion from MIDI to SPMIDI. However, simple MIDI to SP-MIDI reduction algorithms, such as note-stealing, may lose or interrupt important musical information. This paper presents a phrase stealing algorithm that drops the perceptually least important notes when reducing a MIDI file to SPMIDI, and preserves the most important phrases. The phrase stealing algorithm produces SP-MIDI files with an average phrase length of 10 notes, in contrast to the ...

• Type: Journal
• Year: 2006
• Where: IEEEMM
• Authors: Simon Lui, Andrew Horner, Lydia Ayers
• Keywords: IEEEMM 2006, MIDI, Midi File, Mobile Phone