MIDI, or Musical Instrument Digital Interface, is digital information channeled through a software instrument to produce sound. Pictured above are three MIDI tracks, and MIDI regions in green. Under those regions in larger green bars, the MIDI editor in GarageBand allows for fine-tuned editing of the selected MIDI region.
- Selected MIDI Region: Clicking on a MIDI or audio region will display it larger in the editing window when the editor is enabled.
- MIDI Editing Window: Midi notes can be input or deleted, shifted in pitch or time, and trimmed or extended in length in this window using a mouse.
- Piano Roll: A representation of the pitch that each horizontal row of the editor represents. Darker grey stripes represent black keys on the piano, lighter grey stripes represent the white keys.
- Quantization: When recording with the metronome, notes will usually begin near a beat represented by the vertical grid. Quantization moves notes near a grid marker closer to the grid, moving notes that may have been performed slightly out of time towards a more perfect recording.
- Transpose: Moves all selected notes up or down depending on which way the slider is moved. Individual notes can be selected by clicking on them. Multiple notes can be selected by shift+clicking, or clicking and dragging a selection box around the desired notes.
- Piano Roll View: Displays the piano roll and any existing MIDI notes in the region.
- Score View: Converts the MIDI notes into sheet music that can be exported as a PDF.
- Velocity Slider (not pictured): Velocity refers to the volume of a particular note. Notes can be adjusted up or down in volume by selecting them and adjusting the velocity slider. The relative velocity of each note appears as a white bar inside the green MIDI note.
Watch the video below for more information.
