Prefab MidiFilePlayer

MidiFilePlayer is a Prefab useful for playing a midi  file in your application. See Quick Start to understand how to add a MidiFilePlayer in your application.

Also, you can use MidiFilePlayer gameObject in your script to create a more complex interaction. See an example with source code at the end of this page.

Tips:

  • Play once midi file at a time.
  • Several prefabs MidiFileplayer can be added to the scene and can play simultaneously.
  • All the parameters and the functions of the prefab are also available with an API for integration in your script. See here.

Main parameters

Select your Midi in the Inspector and run your application, the Midi is playing . It’s as simple as that ! See below the specific parameters that can be apply.

  • Select Midi: open a popup with all your midi file available in your project. Select one midi to play. Before, add midi files to the local MidiDB (free version comes with a set of midi files for demonstration purpose). See MPTK Midi Setup.
  • Volume: set the default volume of the playing.
  • Transpose: transpose the music by half tones.
  • Play At Startup: if checked, start playing when your application starts.
  • Start Play From First Note: search for the first note in the Midi and plays it immediately. Useful to avoid latency at start.
  • Pause When Focus Loss: Pause the midi playing when the application lost the focus, go in background or application is suspended.
  • Send To Synth: if not checked, Midi file is read by the internal Midi sequencer but no midi event is sent to the Midi synthesizer. Nevertheless, all Midi events are triggering the event OnEventNotesMidi, so you can processing midi events in your script without playing it.
  • Loop On Midi: if check, restart playing automatically when the end of the midi file is reached. The midi file is not reload.

Parameters when running

  • Time / Position current time position of the playing Midi and total length. The time can change if a tempo change is received from the Midi sequencer. The slider can be use to change this position when playing.
  • Ticks / Position current tick position of the playing Midi and total length. The value is independent of the tempo change. The slider can be use to change this position when playing.
  • Play / Pause / Stop / Restart, change the current playing status.
  • Previous / Next load previous or next Midi in the MPTK Midi list.

Foldout Spatialization

First of all, you have to setup Spatialization in Unity See here. Then look at these dedicated settings in the prefab inspector:

MPTK Inspector For Spatialization Parameters

  • Spatialization: if checked, Unity spatializer is enabled.
    • AudioSource setting is modified for playing spatialization algo if a spacializer plugins is defined.
    • A Maestro specific function is able to pause the Midi reader if the distance between the gameobject (which hold this prefab) and the AudioListener is greater than Max Distance.
  • Max Distance: distance for pausing the Midi reader.

Tips:

  • To take advantage of this effect, it’s better to listen with an headphone.
  • Do not mix up “stereo” and “spatialization” effects. The stereo information (pan) comes up from the SoundFont properties. For example: left right panning for a piano is depending on the key position.
    These two effects could counteracted each other. The “pan” properties can be disabled within the foldout “Show Synth Parameters” in inspector. See here Modulator / Pan Change.
  • Don’t forget to setup Unity spatialization See here !

Look also at the dedicated prefab MidiSpatializer (Pro version) able to assign different 3d sound positions by midi channels, by tracks, by instruments. Fly through the music, better with a virtual headsets!!!

Foldout Midi Parameters

  • Quantization: define quantization to remove some imprecision in tempo. With quantization, notes are plays on beats or on fractions of beats.
  • Speed: to play the Midi file. with 1 play at the tempo defined in the Midi file.
  • Tempo Change: enable tempo change from the Midi.
  • Drum Preset Change: enable control change preset for drum. Disabled by default.
  • Keep Notes Off: notes off are not used to play the Midi (duration is used). If you have the need to get Note Off (for example to write a consistent Midi file or process these events in your code), check this option.
  • Log Midi Events: check to have a log for each Midi events when playing.

Foldout Events

Fires actions in your script in relation with the Midi Player. These actions can be define with the inspector or by script with MPTK API.

  • On Event Start Play Midi: start playing the Midi file. Receives the Midi name in parameter as a string.
  • On Event Notes Midi: when a group of notes is ready to be play by the sequencer. Receives a list of MptkEvent in the parameter.
  • On Event End Play Midi: end playing the Midi file. Receives the Midi name in parameter as a string and the reason of the end.

Foldout Midi Info

Display information from the META chunks of the midi file. Enabled only when playing a Midi which contains META data.

Foldout Synth Parameters

The midi synthesizer is based on fluidsynth. It’s an adaption on this well known synth from C to C# for Unity.

Audio Parameters

  • Core Player: if checked, the synthesizer is working on a system thread apart from the main Unity thread: accuracy and latency are better. On top of that, synthesizer is based on a full migration of fluidsynth: sound is better.
    When Core Player is not checked, the legacy mode is enabled (available since the V1). Many AudioSource are used to play each sample and the synth is simplified. Warning, the legacy mode is not compatible with all the MPTK functions. It will be removed with the next major version.
  • Rate Synth Output: defined the rate of the FMOD component in Unity. High rate enhance the quality of the sound but with cost on performance (linear impact). It’s a global parameter for your application. The default value can be also defined with Project Setting/Audio.
  • Buffer Synth Size: defined the size of the FMOD buffer. Small buffer decrease the latency and enhance the accurate of the playing but with a little cost on performance. It’s a global parameter for your application. The default value can be also defined with Project Setting/Audio.
  • Interpolation Method: convert the wave sample to the synth format.
    • None: no interpolation. Just take the sample, which is closest to the playback pointer. Very efficient but questionable quality.
    • Linear: Straight line interpolation. A good balancing. Cost performance: 17% from none interpolation.
    • 4th order: Even Better ! Cost performance: 30%
    • 7th order: Even Better ! Cost performance: 65%

Tip: Changing audio parameters on iOS is disabled because the hardware don’t like changing the default value. Seems to be 24kHz.

Tip: See performance information here

Modulator

  • Log Samples: log to console information about each samples for each notes: sample name, instrument.
  • Pan Change: panoramic setting (stereo) are processed with specific Midi events. On the other hand, the pan information comes up from the SoundFont properties. For example: left right panning for a piano is depending on the key position.
    Uncheck Pan Change if left/right is managed by your application or you have enabled Spatialization.
  • Apply Modulator: apply real time modulator as Pitch Bend and Control Change.
  • Apply Mod LFO: apply LFO modulator (amplitude LFO).
  • Apply Vib LFO: apply LFO vibrator (pitch LFO).
  • Release Same Note: the default behavior of a Midi player is to release a note when the same note is played again. A physical keyboard can’t plays two keys at the same time! It’s possible to change this behavior by unchecking this checkbox.
  • Kill By Exclusive Class: the default behavior of a Midi player is to released a note when a note of the same class is played in the same preset. Class is defined in the SoundFont. Generally, this function is used by drum kit. It’s possible to change this behavior by unchecking this checkbox.

SoundFont Effects [Pro]

Important: by default these effects are not enabled in the prefab. You have to enable them from the inspector (or by script) and enjoy a better sound.

See here for more information.

Performance vs Synthesizer Parameters

These performance has been recorded with an Intel i5-9600K 3.7 GHz CPU.

Foldout Show Default Editor

Some parameters, mainly for the synth, are not defined in the custom inspector. You can change some values for experimentation or debug … at your own risks!

There is also some information about time processing of Midi and Synth. To activate statistics, add these Define Symbols (see here how to):

  • DEBUG_PERF_AUDIO
  • DEBUG_PERF_MIDI
  • DEBUG_STATUS_STAT

Integration of MidiFilePlayer in your script

See TestMidiFilePlayerScripting.cs for the whole example.

using MidiPlayerTK; ... MidiFilePlayer mfp = FindObjectOfType<MidiFilePlayer>(); // Set event by script mfp.OnEventEndPlayMidi.AddListener(EndPlay); mfp.OnEventNotesMidi.AddListener(MidiReadEvents); // Event fired when a midi is ended public void EndPlay(string midiname, EventEndMidiEnum reason) { Debug.LogFormat("End playing {0} reason:{1}", midiname, reason); } // Event fired by MidiFilePlayer when midi notes are available public void MidiReadEvents(List<MPTKEvent> events) { foreach (MPTKEvent midievent in events) ... } void OnGUI() { ... mfp.MPTK_Play(); midiFilePlayer.MPTK_Position = position; ... }
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