"""pygame.midi pygame module for interacting with midi input and output. The midi module can send output to midi devices, and get input from midi devices. It can also list midi devices on the system. Including real midi devices, and virtual ones. It uses the portmidi library. Is portable to which ever platforms portmidi supports (currently windows, OSX, 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. New in pygame 1.9.0. """ #TODO: # - finish writing tests. # - likely as interactive tests... so you'd need to plug in a midi device. # - create a background thread version for input threads. # - that can automatically inject input into the event queue # once the input object is running. Like joysticks. import pygame import pygame.locals import atexit # MIDIIN = pygame.locals.USEREVENT + 10 MIDIOUT = pygame.locals.USEREVENT + 11 _init = False _pypm = None __all__ = [ "Input", "MIDIIN", "MIDIOUT", "MidiException", "Output", "get_count", "get_default_input_id", "get_default_output_id", "get_device_info", "init", "midis2events", "quit", "time", ] __theclasses__ = ["Input", "Output"] def init(): """initialize the midi module pygame.midi.init(): return None Call the initialisation function before using the midi module. It is safe to call this more than once. """ global _init, _pypm if not _init: import pygame.pypm _pypm = pygame.pypm _pypm.Initialize() _init = True atexit.register(quit) def quit(): """uninitialize the midi module pygame.midi.quit(): return None Called automatically atexit if you don't call it. It is safe to call this function more than once. """ global _init, _pypm if _init: # TODO: find all Input and Output classes and close them first? _pypm.Terminate() _init = False del _pypm #del pygame._pypm def _check_init(): if not _init: raise RuntimeError("pygame.midi not initialised.") def get_count(): """gets the number of devices. pygame.midi.get_count(): return num_devices Device ids range from 0 to get_count() -1 """ _check_init() return _pypm.CountDevices() def get_default_input_id(): """gets default input device number pygame.midi.get_default_input_id(): return default_id Return the default device ID or -1 if there are no devices. The result can be passed to the Input()/Ouput() class. On the PC, the user can specify a default device by setting an environment variable. For example, to use device #1. set PM_RECOMMENDED_INPUT_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, and with USB devices that can come and go, using integers is not very reliable for device identification. Under Windows, if PM_RECOMMENDED_OUTPUT_DEVICE (or PM_RECOMMENDED_INPUT_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 and HKEY_LOCAL_MACHINE/SOFTWARE/PortMidi/Recommended_Output_Device for a string. 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, 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. Examples are MMSystem, DirectX (not implemented), ALSA, OSS (not implemented), etc.) At present, the only Win32 interface is "MMSystem", the only Linux interface is "ALSA", and the only Max OS X interface is "CoreMIDI". To specify both the interface and the device name in the registry, separate the two with a comma and a space, e.g.: MMSystem, In USB MidiSport 1x1 In this case, 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. Note: in the current release, the default is simply the first device (the input or output device with the lowest PmDeviceID). """ return _pypm.GetDefaultInputDeviceID() def get_default_output_id(): """gets default output device number pygame.midi.get_default_output_id(): return default_id Return the default device ID or -1 if there are no devices. The result can be passed to the Input()/Ouput() class. On the PC, the user can specify a default device by setting an environment variable. For example, to use device #1. 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, and with USB devices that can come and go, using integers is not very reliable for device identification. Under Windows, if PM_RECOMMENDED_OUTPUT_DEVICE (or PM_RECOMMENDED_INPUT_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 and HKEY_LOCAL_MACHINE/SOFTWARE/PortMidi/Recommended_Output_Device for a string. 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, 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. Examples are MMSystem, DirectX (not implemented), ALSA, OSS (not implemented), etc.) At present, the only Win32 interface is "MMSystem", the only Linux interface is "ALSA", and the only Max OS X interface is "CoreMIDI". To specify both the interface and the device name in the registry, separate the two with a comma and a space, e.g.: MMSystem, In USB MidiSport 1x1 In this case, 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. Note: in the current release, the default is simply the first device (the input or output device with the lowest PmDeviceID). """ _check_init() return _pypm.GetDefaultOutputDeviceID() def get_device_info(an_id): """ returns information about a midi device pygame.midi.get_device_info(an_id): return (interf, name, input, output, opened) interf - a text string describing the device interface, eg 'ALSA'. name - a text string for the name of the device, eg 'Midi Through Port-0' input - 0, or 1 if the device is an input device. output - 0, or 1 if the device is an output device. opened - 0, or 1 if the device is opened. If the id is out of range, the function returns None. """ _check_init() return _pypm.GetDeviceInfo(an_id) class Input(object): """Input is used to get midi input from midi devices. Input(device_id) Input(device_id, buffer_size) buffer_size -the number of input events to be buffered waiting to be read using Input.read() """ def __init__(self, device_id, buffer_size=4096): """ The buffer_size specifies the number of input events to be buffered waiting to be read using Input.read(). """ _check_init() if device_id == -1: raise MidiException("Device id is -1, not a valid output id. -1 usually means there were no default Output devices.") try: r = get_device_info(device_id) except TypeError: raise TypeError("an integer is required") except OverflowError: raise OverflowError("long int too large to convert to int") # and now some nasty looking error checking, to provide nice error # messages to the kind, lovely, midi using people of whereever. if r: interf, name, input, output, opened = r if input: try: self._input = _pypm.Input(device_id, buffer_size) except TypeError: raise TypeError("an integer is required") self.device_id = device_id elif output: raise MidiException("Device id given is not a valid input id, it is an output id.") else: raise MidiException("Device id given is not a valid input id.") else: raise MidiException("Device id invalid, out of range.") def _check_open(self): if self._input is None: raise MidiException("midi not open.") def close(self): """ closes a midi stream, flushing any pending buffers. Input.close(): return None PortMidi attempts to close open streams when the application exits -- this is particularly difficult under Windows. """ _check_init() if not (self._input is None): self._input.Close() self._input = None def read(self, num_events): """reads num_events midi events from the buffer. Input.read(num_events): return midi_event_list Reads from the Input buffer and gives back midi events. [[[status,data1,data2,data3],timestamp], [[status,data1,data2,data3],timestamp],...] """ _check_init() self._check_open() return self._input.Read(num_events) def poll(self): """returns true if there's data, or false if not. Input.poll(): return Bool raises a MidiException on error. """ _check_init() self._check_open() r = self._input.Poll() if r == _pypm.TRUE: return True elif r == _pypm.FALSE: return False else: err_text = GetErrorText(r) raise MidiException( (r, err_text) ) class Output(object): """Output is used to send midi to an output device Output(device_id) Output(device_id, latency = 0) Output(device_id, buffer_size = 4096) Output(device_id, latency, buffer_size) 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. (NOTE: time is measured relative to the time source indicated by time_proc. Timestamps are absolute, not relative delays or offsets.) 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. """ def __init__(self, device_id, latency = 0, buffer_size = 4096): """Output(device_id) Output(device_id, latency = 0) Output(device_id, buffer_size = 4096) Output(device_id, latency, buffer_size) 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. (NOTE: time is measured relative to the time source indicated by time_proc. Timestamps are absolute, not relative delays or offsets.) 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. """ _check_init() self._aborted = 0 if device_id == -1: raise MidiException("Device id is -1, not a valid output id. -1 usually means there were no default Output devices.") try: r = get_device_info(device_id) except TypeError: raise TypeError("an integer is required") except OverflowError: raise OverflowError("long int too large to convert to int") # and now some nasty looking error checking, to provide nice error # messages to the kind, lovely, midi using people of whereever. if r: interf, name, input, output, opened = r if output: try: self._output = _pypm.Output(device_id, latency) except TypeError: raise TypeError("an integer is required") self.device_id = device_id elif input: raise MidiException("Device id given is not a valid output id, it is an input id.") else: raise MidiException("Device id given is not a valid output id.") else: raise MidiException("Device id invalid, out of range.") def _check_open(self): if self._output is None: raise MidiException("midi not open.") if self._aborted: raise MidiException("midi aborted.") def close(self): """ closes a midi stream, flushing any pending buffers. Output.close(): return None PortMidi attempts to close open streams when the application exits -- this is particularly difficult under Windows. """ _check_init() if not (self._output is None): self._output.Close() self._output = None def abort(self): """terminates outgoing messages immediately Output.abort(): return 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. """ _check_init() if self._output: self._output.Abort() self._aborted = 1 def write(self, data): """writes a list of midi data to the Output Output.write(data) writes series of MIDI information in the form of a list: write([[[status <,data1><,data2><,data3>],timestamp], [[status <,data1><,data2><,data3>],timestamp],...]) fields are optional example: choose program change 1 at time 20000 and send note 65 with velocity 100 500 ms later. write([[[0xc0,0,0],20000],[[0x90,60,100],20500]]) notes: 1. timestamps will be ignored if latency = 0. 2. To get a note to play immediately, send MIDI info with timestamp read from function Time. 3. understanding optional data fields: write([[[0xc0,0,0],20000]]) is equivalent to write([[[0xc0],20000]]) Can send up to 1024 elements in your data list, otherwise an IndexError exception is raised. """ _check_init() self._check_open() self._output.Write(data) def write_short(self, status, data1 = 0, data2 = 0): """write_short(status <, data1><, data2>) Output.write_short(status) Output.write_short(status, data1 = 0, data2 = 0) output MIDI information of 3 bytes or less. data fields are optional status byte could be: 0xc0 = program change 0x90 = note on etc. data bytes are optional and assumed 0 if omitted example: note 65 on with velocity 100 write_short(0x90,65,100) """ _check_init() self._check_open() self._output.WriteShort(status, data1, data2) def write_sys_ex(self, when, msg): """writes a timestamped system-exclusive midi message. Output.write_sys_ex(when, msg) msg - can be a *list* or a *string* when - a timestamp in miliseconds example: (assuming o is an onput MIDI stream) o.write_sys_ex(0,'\\xF0\\x7D\\x10\\x11\\x12\\x13\\xF7') is equivalent to o.write_sys_ex(pygame.midi.time(), [0xF0,0x7D,0x10,0x11,0x12,0x13,0xF7]) """ _check_init() self._check_open() self._output.WriteSysEx(when, msg) def note_on(self, note, velocity=None, channel = 0): """turns a midi note on. Note must be off. Output.note_on(note, velocity=None, channel = 0) Turn a note on in the output stream. The note must already be off for this to work correctly. """ if velocity is None: velocity = 0 if not (0 <= channel <= 15): raise ValueError("Channel not between 0 and 15.") self.write_short(0x90+channel, note, velocity) def note_off(self, note, velocity=None, channel = 0): """turns a midi note off. Note must be on. Output.note_off(note, velocity=None, channel = 0) Turn a note off in the output stream. The note must already be on for this to work correctly. """ if velocity is None: velocity = 0 if not (0 <= channel <= 15): raise ValueError("Channel not between 0 and 15.") self.write_short(0x80 + channel, note, velocity) def set_instrument(self, instrument_id, channel = 0): """select an instrument, with a value between 0 and 127 Output.set_instrument(instrument_id, channel = 0) """ if not (0 <= instrument_id <= 127): raise ValueError("Undefined instrument id: %d" % instrument_id) if not (0 <= channel <= 15): raise ValueError("Channel not between 0 and 15.") self.write_short(0xc0+channel, instrument_id) def time(): """returns the current time in ms of the PortMidi timer pygame.midi.time(): return time The time is reset to 0, when the module is inited. """ return _pypm.Time() def midis2events(midis, device_id): """converts midi events to pygame events pygame.midi.midis2events(midis, device_id): return [Event, ...] Takes a sequence of midi events and returns list of pygame events. """ evs = [] for midi in midis: ((status,data1,data2,data3),timestamp) = midi e = pygame.event.Event(MIDIIN, status=status, data1=data1, data2=data2, data3=data3, timestamp=timestamp, vice_id = device_id) evs.append( e ) return evs class MidiException(Exception): """exception that pygame.midi functions and classes can raise MidiException(errno) """ def __init__(self, value): self.parameter = value def __str__(self): return repr(self.parameter)