A toolkit for working with Standard MIDI files
$ pip install miditk-smf
from miditk.smf import MidiFileWriter # Open file for writing in binary mode. with open('minimal.mid', 'wb') as smf: # Create standard MIDI file writer. midi = MidiFileWriter(smf) # Write file and track header for Type 0 file, one track, 96 pulses per # quarter note (ppqn). These are also the default parameter values. midi.header(format=0, num_tracks=1, tick_division=96) midi.start_of_track() # Set tempo to 120 bpm in µsec per quarter note. # When no tempo is set in the MIDI file, sequencers will generally assume # it to be 120 bpm. midi.tempo(int(60000000 / 120)) # Add MIDI events. midi.note_on(channel=0, note=0x40) # Advance 192 ticks (i.e. a half note). midi.update_ticks(192) midi.note_off(channel=0, note=0x40) # End track and midi file. midi.end_of_track() midi.eof()
For more examples, see the Usage examples section below.
miditk-smf is a general-purpose library for the parsing and generation of
Standard MIDI Files (SMF). The package is part of several planned packages
under the common top-level package namespace
miditk. This package mainly
miditk.smf sub-package for handling standard MIDI files.
Additional sub-packages with more specialised MIDI libraries and tools will be
distributed as separate package distributions in the future.
miditk-smf works with Python 2.7, Python 3.4+ and PyPy 2 and 3.
$ pip install miditk-smf
It is provided as a source distribution and a universal Python wheel for all supported Python versions and operating systems. It only depends on the Python standard library and the third-party module six.
- A collection of constants from the MIDI specification used by sub-packages and general data types for working with MIDI events.
- An event-based standard MIDI file (SMF) parsing and generation framework.
- Base event handler classes, which can be sublassed for specialised event handling.
- A collection of functions that converts the special data types used in midi files to and from byte strings.
- The main binary MIDI file data parser.
- Combines the parser with an event handler class.
- An event handler, which stores all MIDI events from a MIDI file in a MidiSequence container class.
- An event handler to write out MIDI events to a Standard MIDI File.
The following section contains a few code examples, which demonstrate several
usage scenarios for the different modules in the package. For more examples see
also the scripts in the
examples directory of the source distribution.
Parsing a standard MIDI file
miditk.smf module provides the
MidiSequence container class, which
uses its own MIDI event handler class to collect all information and events
from parsing a midi file. Use the
MidiSequence.fromfile() class method to
parse a standard MIDI file.
You can then use several convenience methods of the returned
instance to access information about the midi file properties or events.
from miditk.smf import MidiSequence # Do parsing sequence = MidiSequence.fromfile(sys.argv) # Print some info from the MIDI file header, # e.g. number of tracks, events sequence name. print(sequence) # Print a list of events with event type, data and timestamp. sequence.dump_events() # Iterate over all sysex events in track 0. # If track is not specified, sysex_events() yields all sysex events # in all tracks. for ev in sequence.sysex_events(track=0): print "Sysex event (%i bytes) @ %.2f" (len(ev.data), ev.timestamp) # Iterate over all events sorted by timestamp and then track. for ev in sequence.events_by_time(): handle_event(ev)
Changing MIDI events in-stream
The event-based parsing allows to handle MIDI events as they are read (or
received via MIDI in). You need to define a sub-class of
and overwrite only the event handling methods for the events you are
The following example transposes all note on/off events by an octave (i.e. 12 semitones):
import sys from miditk.smf import MidiFileReader, MidiFileWriter # MidiFileWriter is a sub-class of NullMidiEventHandler. class Transposer(MidiFileWriter): """Transpose note values of all note on/off events by 1 octave.""" def note_on(self, channel, note, velocity): super().note_on(self, channel, min(127, note + 12), velocity) def note_off(self, channel, note, velocity): super().note_off(self, channel, min(127, note + 12), velocity) infile = sys.argv.pop(1) outfile = sys.argv.pop(1) # Create the parser and event handler with open(outfile, 'wb') as smf: midiout = Transposer(smf) midiin = MidiFileReader(infile, midiout) # Now do the processing. midiin.read()
Clone the repo:
$ git clone https://github.com/SpotlightKid/miditk-smf.git $ cd miditk-smf
$ pip install tox
Or via your Linux distribution package manager, e.g. on debian/Ubuntu:
$ sudo apt-get install python-tox
Or on Arch Linux:
$ sudo pacman -S python-tox
Run the tests via tox for all Python versions configured in tox.ini:
If all is well, create a new git branch and start hacking and then contribute your changes by opening a pull request on GitHub.
The included Makefile is set up to run several Python static code checking and reporting tools. To print a list of available Makefile targets and the tools they run, simple run:
Then run the Makefile target of your choice, e.g.:
$ make flake8
Unless noted otherwise, these targets run all tools directly, i.e. without tox, which means they need to be installed in your Python environment, preferably in a project-specific virtual environment. To create a virtual environment and install all supported tools and their dependencies run:
$ mkvirtualenv miditk-smf (miditk-smf)$ pip install -r requirements/dev.txt
Package documentation is generated by Sphinx. The documentation can be build with:
$ make docs
After a successful build the documentation index is opened in your web browser.
Authors and License
miditk package is written by Christopher Arndt and licensed under the