Web MIDI API Wrapper

Live Demo

https://dl.dropboxusercontent.com/u/695740/WebMIDIAPIWrapper/index.html

• Mac users: Select "Apple DLS Synth (0.Apple DLS Synth)" for output device.
• Windows users: Select "Microsoft GS Wavetable Synth (0.Microsoft GS Wavetable Synth)" for output device.

In the demo, js/ctrlctrlWebmidilib.js is the main JavaScript file.

What is this?

This script is JavaScript wrapper for developers who wants to play with Musical Instruments and web browser!!

• What is MIDI? -> MIDI@wikipedia
• What is Web MIDI API? -> Web MIDI API@W3C

Purpose of using this Wrapper

MIDI is well defined protocol. But to use the protocol you must learn 7bit code, such as NoteOn: 9nH, NoteOff: 8nH. With using this wrapper you do NOT have to learn those 7bit code. And also, you do NOT have to know about method in Web MIDI API. A thing you must know is really basic JavaScript only!! Therefore, you can easily build MIDI application only with the wrapper and JavaScript !!

Supported MIDI Message (as is 2013 Aug 19)

• NoteOn
• NoteOff
• PitchBend
• Sustain
• Modulation
• AllSoundOff
• ResetAllController
• AllNoteOff

Requirements (as is 2013 Aug 19)

Web MIDI API is NOT fully implemented in browser. Only Chrome Canary accept MIDI input.
So, please install Jazz-Plugin developed by Jazz-Soft.net.

How to use

• clone this repository
• link to the wrapper and Web MIDI API Shim

<script src="[PathToJS]/WebMIDIAPI.js"></script>
<script src="[PathToJS]/WebMIDIAPIWrapper.js"></script>

• create constructor

 var wmaw = new WebMIDIAPIWrapper( false );

• Set an EventHandler for setMidiInputSelect and setMidiOutputSelect

  • setMidiInputSelect : display MIDI input ports, and EventHandler of when MIDI input port is specified
  • setMidiOutputSelect : display MIDI output ports, and EventHandler of when MIDI output port is specified

• Set an EventHandler named onmidimessage inside of setMidiInputSelect EventHandler.

• Do initialization.

wmaw.init();

Method to send MIDI Messages

'sendNoteOn(portNo, ch, note, velocity, time)'
description: send noteOn message to ch of portNo.
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• note: noteNo to noteOn
• velocity : velocity of note
• time: the time at which to begin sending the data to the port

'sendNoteOff(portNo, ch, note, velocity, time)'
description: send noteOff message to ch of portNo.
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• note: noteNo to noteOff
• velocity : velocity of note (some MIDI device accept the value as speed of noteOff)
• time: the time at which to begin sending the data to the port

'sendProgramChange(portNo, ch, programNo, time)'
description: send programchange message to change voice
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• programNo: voice number to change
• time: the time at which to begin sending the data to the port

'setPitchBendValue(portNo, min, max, center)'
description: set the range of the pitch change value.(sometimes -8192 to 8191(center:0), 0 to 16383(center:8192). This value is depends on the MIDI device.)
values:

• portNo: port number to send message
• min: minimum number of pitchbend value
• max: maximum number of pitchbend value
• center: center number of pitchbend value

'sendPitchBend(portNo, ch, value, time)'
description: send pitchbend message by value
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• value: value to change
• time: the time at which to begin sending the data to the port

'sendSustainStatus(portNo, ch, status, time)'
description: send sustain message by status
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• status: "on" or "off"
• time: the time at which to begin sending the data to the port

'sendModulationValue(portNo, ch, value, time)'
description: send modulation message by value
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• value: value to change
• time: the time at which to begin sending the data to the port

'sendAllSoundOff(portNo, ch, time)'
description: send AllSoundOff message to stop all sounds(even sustain and sound reflection) in channel.
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• time: the time at which to begin sending the data to the port

'sendResetAllController(portNo, ch, time)'
description: send ResetAllController to reset all controller(pitchbend, after-touch and so on) to initial value in channel.
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• time: the time at which to begin sending the data to the port

'sendAllNoteOff(portNo, ch, time)'
description: send AllNoteOff message to stop all sounds(sustain and sound reflection are NOTE affected) in channel.
values:

• portNo: port number to send message
• ch: ch number to send message in the port
• time: the time at which to begin sending the data to the port

'sendRaw(portNo, msg, time)'
description: send Raw MIDI message by array.
values:

• portNo: port number to send message
• msg: set MIDI message as array. In the array, either hexadecimal or decimal (even mixture format) is allow to specify. e.g.) [0x80, 72, 120]
• time: the time at which to begin sending the data to the port

'initializePerformanceNow()'
description: Initialize start time.
values: no valuables

License

The Apache License Version 2.0