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Polyphonic Tone Transfer Language: superset of NOKIA's RTTTL, supports polyphony & vibrato

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ptttl is a command-line utility for converting PTTTL and RTTTL files to .wav audio files. ptttl also provides an API for parsing PTTTL and RTTTL files to convert them into usable musical data.

The Polyphonic Tone Text Transfer Language (PTTTL) is a way to describe polyphonic melodies, and is a superset of Nokia's RTTTL format, extending it to enable polyphony and vibrato.

A reference implementation in python is provided for general purpose applications.

API documentation can be found here

Install from pip

pip install -r ptttl
python -m ptttl input.ptttl -f output.wav

Run python -m ptttl -h to see available options.

>>> from ptttl.parser import PTTTLParser
>>> with open('input.pttl', 'r') as fh:
...     ptttl_source = fh.read()
...
>>> parser = PTTTLParser()
>>> ptttl_data = parser.parse(ptttl_source)
>>> ptttl_data
PTTTLData([PTTTLNote(pitch=195.9977, duration=0.5625), PTTTLNote(pitch=195.9977, duration=0.2812), ...], ...)
>>> from ptttl.audio import ptttl_to_wav
>>> with open('input.pttl', 'r') as fh:
...     ptttl_source = fh.read()
...
>>> ptttl_to_wav(ptttl_source, 'output.wav')

A reference implemention written in C is provided, which is suitable for use in embedded applications, under the c_implementation directory.

See the README for the C implementation here.

Because PTTTL is a superset of RTTTL, valid RTTTL strings are also valid PTTTL strings. A parser that properly handles PTTTL can also handle RTTTL.

A PTTTL string is made up of three colon-seperated sections; name section, default values section, and data section.

Whitespace characters, empty lines, and lines beginning with a "#" character are ignored.

The initial "name" section is intended to contain the name of the ringtone in the original RTTTL format. PTTTL requires this field to be present, to maintain backwards compatibility with RTTTL, but places no constraints on its contents.

The very first statement is the default values section, and it is the same as the default values section from the RTTTL format, except with two additional vibrato-related settings:

b=123, d=8, o=4, f=7, v=10
  • b - beat, tempo: tempo in BPM (Beats Per Minute)
  • d - duration: default duration of a note if none is specified
  • o - octave: default octave of a note if none is specified
  • f - frequency: default vibrato frequency if none is specified, in Hz
  • v - variance: default vibrato variance from the main pitch if none is specified, in Hz

The PTTTL data section is just like the RTTTL data section, in that a melody consists of multiple comma-seperated notes to be played sequentially. Unlike RTTTL, PTTTL allows multiple melodys to be defined, separated by the vertical pipe character |, all of which will be played in unison.

The format of a note is identical to that described by the RTTTL format. Each note includes, in sequence; a duration specifier, a standard music note, either a, b, c, d, e, f or g (optionally followed by '#' or 'b' for sharps and flats), and an octave specifier. If no duration or octave specifier are present, the default applies.

Valid values for note duration:

  • 1 - whole note
  • 2 - half note
  • 4 - quarter note
  • 8 - eighth note
  • 16 - sixteenth note
  • 32 - thirty-second note

Dotted rhythm patterns can be formed by adding a period "." either after the note letter (e.g. c#., or c#.5), or after the octave number (e.g. c#5.)

Valid values for note pitch (non case-sensitive):

  • P - rest or pause
  • A
  • A# / Bb
  • B / Cb
  • C
  • C# / Db
  • D
  • D# / Eb
  • E / Fb
  • F / E#
  • F# / Gb
  • G
  • G# / Ab

Valid values for note octave are between 0 and 8.

Optionally, vibrato may be enabled and configured for an individual note. This is done by appending a v to the end of the note, and optionally frequency and variance values seperated by a - character. For example:

  • 4c#v refers to a C# quarter note with vibrato enabled, using default settings
  • 4c#v10-15 refers to a C# quarter note with vibrato enabled, using a vibrato frequency of 10Hz, with a maximum vibrato variance of 15Hz from the main pitch.

Consider the following PTTTL string:

# 123 beats-per-minute, default quarter note, default 4th octave
Test Melody:
b=123, d=4, o=4:

16c, 8p, 16c | 16e, 8p, 16e | 16g5, 8p, 16g5

This would play 3 sixteenth notes simultaneously (C, octave 4; E, octave 4; G, octave 5), followed by an eighth note rest, followed by the same three sixteenth notes again

Note that the above sample is much easier to read if we put each melody on a new line and align the notes in columns. This is the recommended way to write PTTTL:

# Nicely aligned
Test Melody:
b=123, d=4, o=4:

16c,  8p,  16c  |
16e,  8p,  16e  |
16g5, 8p,  16g5

In order to keep things readable for large PTTTL files with multiple concurrent tracks, a semicolon character ; can be used further break up melodies into more practical blocks. Just as the veritcal pipe character | seperates concurrent tracks within a single polyphonic melody, the semicolon character seperates multiple sequential polyphonic melodies within a single data section. Blocks of notes seperated by semicolons will be "stitched together", or concatenated, in the final output.

The semicolon does not affect any of the timings or pitch of the generated tones; it just makes the PTTTL source a bit more readable, and gives you more options for organizing the lines when writing music. Have a look at this larger PTTTL file, with 4 simultaneous melodies, for a good example of why the semicolon is useful:

All Star but it's a Bach chorale:
d=4,o=5,b=100, f=7, v=10:

#some   bo  -   dy      once    told    me      the     world   was     go -

4gb5v,  8db6,   8bb5,   4bb5,   8ab5v,  8gb5,   8gb5,   4b5v,   8bb5,   8bb5 |
4gb4,   8gb4,   8gb4,   4gb4,   8f4,    8gb4,   8gb4,   4ab4,   8g4,    8g4  |
4gb4,   8bb4,   8db5,   4db5,   8db5,   8db5,   8db5,   4eb5,   8db5,   8db5 |
4gb3,   8gb3,   8gb3,   4gb3,   8ab3,   8bb3,   8bb3,   4ab3,   8bb3,   8bb3 ;



#-na    roll    me,     I       aint    the     sharp - est     tool    in

8ab5,   8ab5v,  4gb5,   8gb5v,  8db6v,  8bb5,   8bb5v,  8ab5,   8ab5v,  8gb5 |
8ab4,   8eb4,   4eb4,   8eb4,   8gb4,   8gb4,   8gb4,   8f4,    8f4,    8eb4 |
8eb5,   8eb5,   4b4,    8b4,    8db5,   8db5,   8db5,   8b4,    8b4,    8bb4 |
8b3,    8b3,    4eb4,   8b3,    8bb3,   8b3,    8db4,   8db4,   8d4,    8eb4 ;



#the    she  -  ed,             she     was     loo  -  king    kind    of

8gb5,   4eb5v,  8db5v,  2p,     8gb5,   8gb5,   8db6v,  8bb5,   8bb5,   8ab5 |
8eb4,   4b3,    8ab3,   2p,     8db4,   8db4,   8gb4,   8gb4,   8gb4,   8f4  |
8bb4,   4gb4,   8f4,    2p,     8gb4,   8gb4,   8bb4,   8db5,   8db5,   8db5 |
8db4,   4b3,    8ab3,   2p,     8bb3,   8ab3,   8gb3,   8gb3,   8gb3,   8ab3 ;



#dumb   with    her     fing  - er      and     her     thumb   in      the

8ab5v,  8gb5,   8gb5,   4b5v,   8bb5,   8bb5,   8ab5,   8ab5v,  8gb5,   8gb5 |
8gb4,   8gb4,   8eb4,   4eb4,   8eb4,   8eb4,   8eb4,   8eb4,   8eb4,   8eb4 |
8db5,   8db5,   8bb4,   4ab4,   8db5,   8db5,   8b4,    8b4,    8b4,    8b4  |
8bb3,   8bb3,   8eb4,   4ab4,   8g4,    8g4,    8ab4,   8ab3,   8b3,    8b3  ;



#shape  of      an      L       on      her     for  -  head

4db6v,  8bb5v,  8bb5v,  4ab5v,  8gb5,   8gb5,   4ab5v,  8eb5 |
4gb4,   8gb4,   8gb4,   4f4,    8f4,    8eb4,   4eb4,   8b3  |
4db5,   8db5,   8db5,   4b4,    8bb4,   8bb4,   4b4,    8ab4 |
4bb3,   8b3,    8db4,   4d4,    8eb4,   8eb4 ,  4ab4,   8ab4