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:mod:`pygame.midi`

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.. include:: common.txt

:mod:pygame.midi

.. module:: pygame.midi :synopsis: pygame module for interacting with midi input and output.

| :sl:pygame module for interacting with midi input and output.

.. versionadded:: 1.9.0

The midi module can send output to midi devices and get input from midi devices. It can also list midi devices on the system.

The midi module supports real and virtual midi devices.

It uses the portmidi library. Is portable to which ever platforms portmidi supports (currently Windows, Mac OS X, and Linux).

This uses pyportmidi for now, but may use its own bindings at some point in the future. The pyportmidi bindings are included with pygame.

|

.. versionadded:: 2.0.0

These are pygame events (:mod:pygame.event) reserved for midi use. The MIDIIN event is used by :func:pygame.midi.midis2events when converting midi events to pygame events.

::

MIDIIN MIDIOUT

|

.. function:: init

| :sl:initialize the midi module | :sg:init() -> None

Initializes the :mod:pygame.midi module. Must be called before using the :mod:pygame.midi module.

It is safe to call this more than once.

.. ## pygame.midi.init ##

.. function:: quit

| :sl:uninitialize the midi module | :sg:quit() -> None

Uninitializes the :mod:pygame.midi module. If :func:pygame.midi.init was called to initialize the :mod:pygame.midi module, then this function will be called automatically when your program exits.

It is safe to call this function more than once.

.. ## pygame.midi.quit ##

.. function:: get_init

| :sl:returns True if the midi module is currently initialized | :sg:get_init() -> bool

Gets the initialization state of the :mod:pygame.midi module.

:returns: True if the :mod:pygame.midi module is currently initialized. :rtype: bool

.. versionadded:: 1.9.5

.. ## pygame.midi.get_init ##

.. class:: Input

| :sl:Input is used to get midi input from midi devices. | :sg:Input(device_id) -> None | :sg:Input(device_id, buffer_size) -> None

:param int device_id: midi device id :param int buffer_size: (optional) the number of input events to be buffered

.. method:: close

  | :sl:`closes a midi stream, flushing any pending buffers.`
  | :sg:`close() -> None`

  PortMidi attempts to close open streams when the application exits.

  .. note:: This is particularly difficult under Windows.

  .. ## Input.close ##

.. method:: poll

  | :sl:`returns True if there's data, or False if not.`
  | :sg:`poll() -> bool`

  Used to indicate if any data exists.

  :returns: ``True`` if there is data, ``False`` otherwise
  :rtype: bool

  :raises MidiException: on error

  .. ## Input.poll ##

.. method:: read

  | :sl:`reads num_events midi events from the buffer.`
  | :sg:`read(num_events) -> midi_event_list`

  Reads from the input buffer and gives back midi events.

  :param int num_events: number of input events to read

  :returns: the format for midi_event_list is
     ``[[[status, data1, data2, data3], timestamp], ...]``
  :rtype: list

  .. ## Input.read ##

.. ## pygame.midi.Input ##

.. class:: Output

| :sl:Output is used to send midi to an output device | :sg:Output(device_id) -> None | :sg:Output(device_id, latency=0) -> None | :sg:Output(device_id, buffer_size=256) -> None | :sg:Output(device_id, latency, buffer_size) -> None

The buffer_size specifies the number of output events to be buffered waiting for output. In some cases (see below) PortMidi does not buffer output at all and merely passes data to a lower-level API, in which case buffersize is ignored.

latency is the delay in milliseconds applied to timestamps to determine when the output should actually occur. If latency is <<0, 0 is assumed.

If latency is zero, timestamps are ignored and all output is delivered immediately. If latency is greater than zero, output is delayed until the message timestamp plus the latency. In some cases, PortMidi can obtain better timing than your application by passing timestamps along to the device driver or hardware. Latency may also help you to synchronize midi data to audio data by matching midi latency to the audio buffer latency.

.. note:: Time is measured relative to the time source indicated by time_proc. Timestamps are absolute, not relative delays or offsets.

.. method:: abort

  | :sl:`terminates outgoing messages immediately`
  | :sg:`abort() -> None`

  The caller should immediately close the output port; this call may result
  in transmission of a partial midi message. There is no abort for Midi
  input because the user can simply ignore messages in the buffer and close
  an input device at any time.

  .. ## Output.abort ##

.. method:: close

  | :sl:`closes a midi stream, flushing any pending buffers.`
  | :sg:`close() -> None`

  PortMidi attempts to close open streams when the application exits.

  .. note:: This is particularly difficult under Windows.

  .. ## Output.close ##

.. method:: note_off

  | :sl:`turns a midi note off (note must be on)`
  | :sg:`note_off(note, velocity=None, channel=0) -> None`

  Turn a note off in the output stream. The note must already be on for
  this to work correctly.

  .. ## Output.note_off ##

.. method:: note_on

  | :sl:`turns a midi note on (note must be off)`
  | :sg:`note_on(note, velocity=None, channel=0) -> None`

  Turn a note on in the output stream. The note must already be off for
  this to work correctly.

  .. ## Output.note_on ##

.. method:: set_instrument

  | :sl:`select an instrument, with a value between 0 and 127`
  | :sg:`set_instrument(instrument_id, channel=0) -> None`

  Select an instrument.

  .. ## Output.set_instrument ##

.. method:: pitch_bend

  | :sl:`modify the pitch of a channel.`
  | :sg:`set_instrument(value=0, channel=0) -> None`

  Adjust the pitch of a channel. The value is a signed integer
  from -8192 to +8191. For example, 0 means "no change", +4096 is
  typically a semitone higher, and -8192 is 1 whole tone lower (though
  the musical range corresponding to the pitch bend range can also be
  changed in some synthesizers).

  If no value is given, the pitch bend is returned to "no change".

  .. versionadded:: 1.9.4

.. method:: write

  | :sl:`writes a list of midi data to the Output`
  | :sg:`write(data) -> None`

  Writes series of MIDI information in the form of a list.

  :param list data: data to write, the expected format is
     ``[[[status, data1=0, data2=0, ...], timestamp], ...]``
     with the ``data#`` fields being optional

  :raises IndexError: if more than 1024 elements in the data list

  Example:
  ::

     # Program change at time 20000 and 500ms later send note 65 with
     # velocity 100.
     write([[[0xc0, 0, 0], 20000], [[0x90, 60, 100], 20500]])

  .. note::
     - Timestamps will be ignored if latency = 0
     - To get a note to play immediately, send MIDI info with timestamp
       read from function Time
     - Optional data fields: ``write([[[0xc0, 0, 0], 20000]])`` is
       equivalent to ``write([[[0xc0], 20000]])``

  .. ## Output.write ##

.. method:: write_short

  | :sl:`writes up to 3 bytes of midi data to the Output`
  | :sg:`write_short(status) -> None`
  | :sg:`write_short(status, data1=0, data2=0) -> None`

  Output MIDI information of 3 bytes or less. The ``data`` fields are
  optional and assumed to be 0 if omitted.

  Examples of status byte values:
  ::

     0xc0  # program change
     0x90  # note on
     # etc.

  Example:
  ::

     # note 65 on with velocity 100
     write_short(0x90, 65, 100)

  .. ## Output.write_short ##

.. method:: write_sys_ex

  | :sl:`writes a timestamped system-exclusive midi message.`
  | :sg:`write_sys_ex(when, msg) -> None`

  Writes a timestamped system-exclusive midi message.

  :param msg: midi message
  :type msg: list[int] or str
  :param when: timestamp in milliseconds

  Example:
  ::

     midi_output.write_sys_ex(0, '\xF0\x7D\x10\x11\x12\x13\xF7')

     # is equivalent to

     midi_output.write_sys_ex(pygame.midi.time(),
                              [0xF0, 0x7D, 0x10, 0x11, 0x12, 0x13, 0xF7])

  .. ## Output.write_sys_ex ##

.. ## pygame.midi.Output ##

.. function:: get_count

| :sl:gets the number of devices. | :sg:get_count() -> num_devices

Device ids range from 0 to get_count() - 1

.. ## pygame.midi.get_count ##

.. function:: get_default_input_id

| :sl:gets default input device number | :sg:get_default_input_id() -> default_id

The following describes the usage details for this function and the :func:get_default_output_id function.

Return the default device ID or -1 if there are no devices. The result can be passed to the :class:Input/:class:Output class.

On a PC the user can specify a default device by setting an environment variable. To use device #1, for example: ::

  set PM_RECOMMENDED_INPUT_DEVICE=1
  or
  set PM_RECOMMENDED_OUTPUT_DEVICE=1

The user should first determine the available device ID by using the supplied application "testin" or "testout".

In general, the registry is a better place for this kind of info. With USB devices that can come and go, using integers is not very reliable for device identification. Under Windows, if PM_RECOMMENDED_INPUT_DEVICE (or PM_RECOMMENDED_OUTPUT_DEVICE) is NOT found in the environment, then the default device is obtained by looking for a string in the registry under: ::

  HKEY_LOCAL_MACHINE/SOFTWARE/PortMidi/Recommended_Input_Device
  or
  HKEY_LOCAL_MACHINE/SOFTWARE/PortMidi/Recommended_Output_Device

The number of the first device with a substring that matches the string exactly is returned. For example, if the string in the registry is "USB" and device 1 is named "In USB MidiSport 1x1", then that will be the default input because it contains the string "USB".

In addition to the name, :func:get_device_info() returns "interf", which is the interface name. The "interface" is the underlying software system or API used by PortMidi to access devices. Supported interfaces: ::

  MMSystem   # the only Win32 interface currently supported
  ALSA       # the only Linux interface currently supported
  CoreMIDI   # the only Mac OS X interface currently supported
  # DirectX - not implemented
  # OSS     - not implemented

To specify both the interface and the device name in the registry, separate the two with a comma and a space. The string before the comma must be a substring of the "interf" string and the string after the space must be a substring of the "name" name string in order to match the device. e.g.: ::

  MMSystem, In USB MidiSport 1x1

.. note:: In the current release, the default is simply the first device (the input or output device with the lowest PmDeviceID).

.. ## pygame.midi.get_default_input_id ##

.. function:: get_default_output_id

| :sl:gets default output device number | :sg:get_default_output_id() -> default_id

See :func:get_default_input_id for usage details.

.. ## pygame.midi.get_default_output_id ##

.. function:: get_device_info

| :sl:returns information about a midi device | :sg:get_device_info(an_id) -> (interf, name, input, output, opened) | :sg:get_device_info(an_id) -> None

Gets the device info for a given id.

:param int an_id: id of the midi device being queried

:returns: if the id is out of range None is returned, otherwise a tuple of (interf, name, input, output, opened) is returned.

     - interf: string describing the device interface (e.g. 'ALSA')
     - name: string name of the device (e.g. 'Midi Through Port-0')
     - input: 1 if the device is an input device, otherwise 0
     - output: 1 if the device is an output device, otherwise 0
     - opened: 1 if the device is opened, otherwise 0

:rtype: tuple or None

.. ## pygame.midi.get_device_info ##

.. function:: midis2events

| :sl:converts midi events to pygame events | :sg:midis2events(midi_events, device_id) -> [Event, ...]

Takes a sequence of midi events and returns list of pygame events.

The midi_events data is expected to be a sequence of ((status, data1, data2, data3), timestamp) midi events (all values required).

:returns: a list of pygame events of event type MIDIIN :rtype: list

.. ## pygame.midi.midis2events ##

.. function:: time

| :sl:returns the current time in ms of the PortMidi timer | :sg:time() -> time

The time is reset to 0 when the :mod:pygame.midi module is initialized.

.. ## pygame.midi.time ##

.. function:: frequency_to_midi

| :sl:Converts a frequency into a MIDI note. Rounds to the closest midi note. | :sg:frequency_to_midi(midi_note) -> midi_note

example: ::

   frequency_to_midi(27.5) == 21

.. versionadded:: 1.9.5

.. ## pygame.midi.frequency_to_midi ##

.. function:: midi_to_frequency

| :sl:Converts a midi note to a frequency. | :sg:midi_to_frequency(midi_note) -> frequency

example: ::

   midi_to_frequency(21) == 27.5

.. versionadded:: 1.9.5

.. ## pygame.midi.midi_to_frequency ##

.. function:: midi_to_ansi_note

| :sl:Returns the Ansi Note name for a midi number. | :sg:midi_to_ansi_note(midi_note) -> ansi_note

example: ::

   midi_to_ansi_note(21) == 'A0'

.. versionadded:: 1.9.5

.. ## pygame.midi.midi_to_ansi_note ##

.. exception:: MidiException

| :sl:exception that pygame.midi functions and classes can raise | :sg:MidiException(errno) -> None

.. ## pygame.midi.MidiException ##

.. ## pygame.midi ##