For details and minor changes, please see the version control log messages.

2017-04-21 version 1.1.0

Project infrastructure:
  • Updated project homepage URL; copyright year and link to docs in readme.
  • Added script to automate updating github pages docs.
Enhancements / Changes:
  • Synced with upstream RtMidi (2.1.1-907a94c).
  • Applied patch from This means that when using the ALSA API port names are reported in the form <client name>:<port name> <port id> (this change was actually already in version 1.0.0).
  • Added new MidiIn / MidiOut method is_port_open.
  • MidiIn / MidiOut constructors and open_port / open_virtual_port methods now raise TypeError when an invalid type is passed as the client resp. port name.
  • Various small documentation improvements.
  • Basic examples: some clean-up, more comments, updated API usage.
  • Added new advanced example script
  • Added new advanced example script
  • added command line param to set controller number.
  • midi2command: Fixed wrong mock lru_cache substitution for Python < 3.2.

2016-11-07 version 1.0.0

Project infrastructure:
  • Added automatic documentation publishing on
  • Added auto docs for MidiIn/MidiOut classes to sphinx docs.
  • Removed pre-release related information from installation docs.
  • Added generated INSTALL.rst to repo to make ReadTheDocs integration work.
  • Added new example script

2016-10-09 version 1.0.0rc1

Project infrastructure:
  • Moved repository to Github.
  • midiutil.open_midiport:
    • Correctly report and log I/O direction and instance type.
    • Fix naming of virtual port.
Enhancements / Changes:
  • Synced with upstream RtMidi (2.1.1-399a8ee).
  • midiutil:
    • The function midiutil.open_port has been renamed to open_midiport.
    • Added convenience functions open_midiinput and open_midioutput, which wrap open_midiport.
    • RtMidi API to use can be specified via the RTMIDI_API environment variable. Only used when API_UNSPECIFIED is passed for the api argument. Value should be one of the API_* constant names with out the API_ prefix, e.g. UNIX_JACK for the Jack API.
  • Cython wrapper class hierarchy restructured to better match the underlying C++ classes and remove code duplication.
  • Some source code re-ordering was done.
  • Added basic structure and initial content of Sphinx documentation.
  • Documented exceptions raised by MidiIn/Out.open_[virtual_]port().
  • Some docstring corrections and formatting fixes.
  • Simplified by throwing out old compatibility stuff.
  • Explicitly call PyEval_InitThreads from Cython code instead of using undocumented compiler macro.
  • Moved osc2midi example into its own repository at
  • Add new sequencer example.
  • Add new noteon2osc example.
  • midifilter:
    • Moved to, removed old code and fixed command line args access.
    • Streamlined event matching.
    • Added CCToBankChange filter.
    • Queue module renamed to queue in Python 3.
    • Fixed opening of output port erroneously used "input".
    • Fixed positional command line args handling.
    • Set command name for argparse.
  • midi2command:
    • Added README.
    • Added command line option to select backend API.
    • Catch errors when opening port.
    • Set client and port name.
    • Cache command lookup (Python 3.2+ only).
  • sysexsaver:
    • Moved to, some refactoring.
    • Fixed wrong entry for manufacturer (0, 32, 81).
    • Moved module level code into main function.
    • Include model name in output file, if possible.
  • drumseq:
    • Fixed global access in Sequencer class.
    • Use args.FileType for pattern command line args.

2014-06-11 version 0.5b1

  • Synced RtMidi code with git repo @ 2c7a6664d6, which fixed several issues (see
  • MidiIn/Out.open_virtual_port returns self for context manager support, consistent with MidiIn/Out.open_port.
  • Fix Python <= 2.6 incompatible encode method call (python-rtmidi officially only supports Python >= 2.7). Thanks to Michiel Overtoom for reporting this.
  • Respect passed MIDI api when requesting MidiOut instance from midiutil.open_midiport.
Enhancements / Changes:
  • Support for Windows Kernel Streaming API was removed in RtMidi (it was broken anyway) and consequently in python-rtmidi as well.
  • Raise RtMidiError exception when trying to open a (virtual) port on a MidiIn/Out instance that already has an open (virtual) port.
  • Add some common synonyms for MIDI events and controllers and some source comments about controller usage to midiconstants module.
  • Fix and clarify queue_size_limit default value in docstrings
  • Various docstring consistency improvements and minor fixes.
  • New example script, which executes external commands on reception of configurable MIDI events, with example configuration.
  • New example directory drumseq with a simple drum pattern sequencer and example drum patterns. Thanks to Michiel Overtoom for the original script!

2013-11-10 version 0.4.3b1

  • Add numeric suffix to version number to comply with PEP 440.
  • Add missing to source distribution.
  • Set default setuptools version in to 1.3.2, which contains fix for bug #99 mentioned below.
  • Add note to installation guide about required --pre option with pip.

2013-11-07 version 0.4.2b

  • Add missing API_* constant to list of exported names of _rtmidi module.
Enhancements / Changes:
  • Change default value of encoding argument of get_ports and get_port_name methods to “auto”, which selects appropriate encoding based on system and backend API used.
  • Add api parameter to midiutil.open_midiport function to select backend API.
  • Make client name for MidiOut and `` MidiIn`` different again, because some backend APIs might require unique client names.
  • Include workaround for setuptools bug (see bitbucket issue #99) in setup file.
  • Add custom distutils command to fill placeholders in template with release meta data.
  • Setuptools is now required, pure distutils won’t work anymore, so removing the fallback import of setup from distutils.

2013-11-05 version 0.4.1b

  • Include missing _rtmidi.cpp file in source distribution.
  • Fill in release data placeholders in INSTALL.rst.

2013-11-05 version 0.4b

  • Fix string conversion in constructors and open_* methods.
  • Change default value queue_size_limit argument to MidiIn constructor to 1024.
  • Update version number in RtMidi.cpp/h to reflect actual code state.
Enhancements / Changes:
  • Elevated development status to beta.
  • Allow MidiIn/Out.open_port methods to be used with the with statement and the port will be closed at the end of the block.
  • MidiIn/MidiOut and open*() methods: allow to specify None as client or port name to get the default names.
  • Move midiconstants module from examples into rtmidi package and added midiutil module.
  • midiutils.open_midiport:
    • Allow to pass (substring of) port name as alternative to port number.
    • Re-raise EOFError and KeyboardInterrupt instead of using sys.exit().
    • Add client_name and port_name arguments.
    • Add use_virtual argument (default False) to request opening of a virtual MIDI port.
    • Add interactive keyword argument (default True) to disable interactive prompt for port.
  • Raise NotImplemented error when trying to open a virtual port with Windows MultiMedia API.
  • Change default name of virtual ports.
  • Re-organize package description and installation instructions into several files and add separate text files with changelog and license information.
  • Add detailed instructions for compiling from source on Windows
  • Add docstrings to all methods and functions in _rtmidi module.
  • Add docstring for midiutils.open_midiport function.
  • Add new example package osc2midi, a simple, uni-directional OSC to MIDI mapper.
  • New example script to demonstrate sending of MIDI system exclusive messages.
  • New example script to demonstrate sending of MIDI control change messages.
  • New sysexsaver example.
  • Convert midifilter example script into a package.
  • Upgrade from optparse to argparse in example scripts.
  • Enable logging in test scripts.
  • Switch from distribute back to setuptools.
  • Include in source distribution.
  • Include examples in source distribution.
  • Install osc2midi example as package and command line script.
  • Enable C++ exceptions on Windows build.

2013-01-23 version 0.3.1a

  • Increase sysex input buffer size for WinMM API again to 8192 (8k) bytes. Requested by Martin Tarenskeen.

2013-01-14 version 0.3a

Bug fixes:
  • Add encoding parameter to get_port_name methods of MidiIn and MidiOut to be able to handle non-UTF-8 port names, e.g. on Windows (reported by Pierre Castellotti).
  • Add encoding parameter to get_ports method as well and pass it through to get_port_name. Use it in the test scripts.
  • Increase sysex input buffer size for WinMM API to 4096 bytes.
  • Add new example script.
  • Add setuptools/distribute support.

2012-07-22 version 0.2a

Bug fixes:
  • Fix uninitialized pointer bug in RtMidi.cpp in ‘MidiOutJack’ class, which caused a warning in the jack process callback when creating a MidiOut instance with the JACK API.
  • testmidiin_*.py: fix superfluous decoding of port name (caused error with Python 3).
  • Simplify some code, some things gleaned from rtmidi_python.
  • Documentation typo fixes and more information on Windows compilation.
  • Enhancements in test scripts:
    • Catch exceptions when creating port.
    • test_midiin_*.py:
      • Better error message for missing/invalid port number.
      • Show how to convert event delta time into absolute time when receiving input.
  • Building on OS X 10.6.9 with CoreMIDI and JACK for OS X successfully tested and test run without errors.
  • WinMM support now compiles with Visual Studio 2008 Express and tests work under Windows XP SP3 32-bit.
  • Add command line option to exclude WinMM or WinKS API from compilation.
  • Add missing extra_compile_args to Extension kwargs in setup file.
  • Add library_dirs to Extension kwargs in setup file.
  • Use -frtti compiler option on OS X (neccessary on 10.7?).
  • Fix file name conflict on case-insensitive file systems by prefixing rtmidi.{pyx,cpp} with an underscore
  • Provide correct compiler flags for compiling with Windows MultiMedia API.
  • Adapt windows library and include path for Visual Studio 2008 Express.
  • add support for compiling with Windows Kernel Streaming API (does not not compile due to syntax errors in RtMidi.cpp yet).

2012-07-13 version 0.1a

First public release.