forked from s444420/AL-2020
729 lines
23 KiB
Python
729 lines
23 KiB
Python
"""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 atexit
|
|
import math
|
|
|
|
import pygame
|
|
import pygame.locals
|
|
|
|
|
|
|
|
#
|
|
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",
|
|
"get_init",
|
|
"time",
|
|
"frequency_to_midi",
|
|
"midi_to_frequency",
|
|
"midi_to_ansi_note",
|
|
]
|
|
|
|
__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 get_init():
|
|
"""returns True if the midi module is currently initialized
|
|
pygame.midi.get_init(): return bool
|
|
|
|
Returns True if the pygame.midi module is currently initialized.
|
|
|
|
New in pygame 1.9.5.
|
|
"""
|
|
return _init
|
|
|
|
|
|
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],...])
|
|
<data> 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, channel=0):
|
|
"""turns a midi note on. Note must be off.
|
|
Output.note_on(note, velocity, channel=0)
|
|
|
|
note is an integer from 0 to 127
|
|
velocity is an integer from 0 to 127
|
|
channel is an integer from 0 to 15
|
|
|
|
Turn a note on in the output stream. The note must already
|
|
be off for this to work correctly.
|
|
"""
|
|
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=0, channel=0):
|
|
"""turns a midi note off. Note must be on.
|
|
Output.note_off(note, velocity=0, channel=0)
|
|
|
|
note is an integer from 0 to 127
|
|
velocity is an integer from 0 to 127 (release velocity)
|
|
channel is an integer from 0 to 15
|
|
|
|
Turn a note off in the output stream. The note must already
|
|
be on for this to work correctly.
|
|
"""
|
|
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 for a channel, with a value between 0 and 127
|
|
Output.set_instrument(instrument_id, channel=0)
|
|
|
|
Also called "patch change" or "program change".
|
|
"""
|
|
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 pitch_bend(self, value=0, channel=0):
|
|
"""modify the pitch of a channel.
|
|
Output.pitch_bend(value=0, channel=0)
|
|
|
|
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".
|
|
"""
|
|
if not (0 <= channel <= 15):
|
|
raise ValueError("Channel not between 0 and 15.")
|
|
|
|
if not (-8192 <= value <= 8191):
|
|
raise ValueError("Pitch bend value must be between "
|
|
"-8192 and +8191, not %d." % value)
|
|
|
|
# "The 14 bit value of the pitch bend is defined so that a value of
|
|
# 0x2000 is the center corresponding to the normal pitch of the note
|
|
# (no pitch change)." so value=0 should send 0x2000
|
|
value = value + 0x2000
|
|
LSB = value & 0x7f # keep least 7 bits
|
|
MSB = value >> 7
|
|
self.write_short(0xe0 + channel, LSB, MSB)
|
|
|
|
|
|
|
|
"""
|
|
MIDI commands
|
|
|
|
0x80 Note Off (note_off)
|
|
0x90 Note On (note_on)
|
|
0xA0 Aftertouch
|
|
0xB0 Continuous controller
|
|
0xC0 Patch change (set_instrument?)
|
|
0xD0 Channel Pressure
|
|
0xE0 Pitch bend
|
|
0xF0 (non-musical commands)
|
|
"""
|
|
|
|
|
|
|
|
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)
|
|
|
|
|
|
|
|
def frequency_to_midi(freqency):
|
|
""" converts a frequency into a MIDI note.
|
|
|
|
Rounds to the closest midi note.
|
|
|
|
::Examples::
|
|
|
|
>>> frequency_to_midi(27.5)
|
|
21
|
|
>>> frequency_to_midi(36.7)
|
|
26
|
|
>>> frequency_to_midi(4186.0)
|
|
108
|
|
"""
|
|
return int(
|
|
round(
|
|
69 + (
|
|
12 * math.log(freqency / 440.0)
|
|
) / math.log(2)
|
|
)
|
|
)
|
|
|
|
def midi_to_frequency(midi_note):
|
|
""" Converts a midi note to a frequency.
|
|
|
|
::Examples::
|
|
|
|
>>> midi_to_frequency(21)
|
|
27.5
|
|
>>> midi_to_frequency(26)
|
|
36.7
|
|
>>> midi_to_frequency(108)
|
|
4186.0
|
|
"""
|
|
return round(440.0 * 2 ** ((midi_note - 69) * (1./12.)), 1)
|
|
|
|
def midi_to_ansi_note(midi_note):
|
|
""" returns the Ansi Note name for a midi number.
|
|
|
|
::Examples::
|
|
|
|
>>> midi_to_ansi_note(21)
|
|
'A0'
|
|
>>> midi_to_ansi_note(102)
|
|
'F#7'
|
|
>>> midi_to_ansi_note(108)
|
|
'C8'
|
|
"""
|
|
notes = ['A', 'A#', 'B', 'C', 'C#', 'D', 'D#', 'E', 'F', 'F#', 'G', 'G#']
|
|
num_notes = 12
|
|
note_name = notes[int(((midi_note - 21) % num_notes))]
|
|
note_number = int(round(((midi_note - 21) / 11.0)))
|
|
return '%s%s' % (note_name, note_number)
|