Provided by: midicsv_1.1+dfsg.1-1build1_amd64 
NAME
midicsv - MIDI Comma-Separated Value (CSV) file format
DESCRIPTION
The midicsv and csvmidi programs permit you to intertranslate standard MIDI files and comma-separated
value (CSV) files. These CSV files preserve all information in the MIDI file, and may be loaded into
spreadsheet and database programs or easily manipulated with text processing tools. This document
describes the CSV representation of MIDI files written by midicsv and read by csvmidi. Readers are
assumed to understand the structure, terminology, and contents of MIDI files-please refer to a MIDI file
reference for details.
RECORD STRUCTURE
Each record in the CSV representation of a MIDI contains at least three fields:
Track Numeric field identifying the track to which this record belongs. Tracks of MIDI data are
numbered starting at 1. Track 0 is reserved for file header, information, and end of file
records.
Time Absolute time, in terms of MIDI clocks, at which this event occurs. Meta-events for which time
is not meaningful (for example, song title, copyright information, etc.) have an absolute time
of 0.
Type Name identifying the type of the record. Record types are text consisting of upper and lower
case letters and the underscore (``_''), contain no embedded spaces, and are not enclosed in
quotes. csvmidi ignores upper/lower case in the Type field; the specifications ``Note_on_c'',
``Note_On_C'', and ``NOTE_ON_C'' are considered identical.
Records in the CSV file are sorted first by the track number, then by time. Out of order records will be
discarded with an error message from csvmidi. Following the three required fields are parameter fields
which depend upon the Type; some Types take no parameters. Each Type and its parameter fields is
discussed below.
Any line with an initial nonblank character of ``#'' or ``;'' is ignored; either delimiter may be used to
introduce comments in a CSV file. Only full-line comments are permitted; you cannot use these delimiters
to terminate scanning of a regular data record. Completely blank lines are ignored.
File Structure Records
0, 0, Header, format, nTracks, division
The first record of a CSV MIDI file is always the Header record. Parameters are format: the MIDI
file type (0, 1, or 2), nTracks: the number of tracks in the file, and division: the number of clock
pulses per quarter note. The Track and Time fields are always zero.
0, 0, End_of_file
The last record in a CSV MIDI file is always an End_of_file record. Its Track and Time fields are
always zero.
Track, 0, Start_track
A Start_track record marks the start of a new track, with the Track field giving the track number.
All records between the Start_track record and the matching End_track will have the same Track
field.
Track, Time, End_track
An End_track marks the end of events for the specified Track. The Time field gives the total
duration of the track, which will be identical to the Time in the last event before the End_track.
File Meta-Events
The following events occur within MIDI tracks and specify various kinds of information and actions. They
may appear at any time within the track. Those which provide general information for which time is not
relevant usually appear at the start of the track with Time zero, but this is not a requirement.
Many of these meta-events include a text string argument. Text strings are output in CSV records
enclosed in ASCII double quote (") characters. Quote characters embedded within strings are represented
by two consecutive quotes. Non-graphic characters in the ISO 8859/1 Latin 1 set are output as a
backslash followed by their three digit octal character code. Two consecutive backslashes denote a
literal backslash in the string. Strings in MIDI files can be extremely long, theoretically as many as
2**28-1 characters; programs which process MIDI CSV files should take care to avoid buffer overflows or
truncation resulting from lines containing long string items. All meta-events which take a text argument
are identified by a suffix of ``_t''.
Track, Time, Title_t, "Text"
The Text specifies the title of the track or sequence. The first Title meta-event in a type 0
MIDI file, or in the first track of a type 1 file gives the name of the work. Subsequent Title
meta-events in other tracks give the names of those tracks.
Track, Time, Copyright_t, "Text"
The Text specifies copyright information for the sequence. This is usually placed at time 0 of
the first track in the sequence.
Track, Time, Instrument_name_t, "Text"
The Text names the instrument intended to play the contents of this track, This is usually placed
at time 0 of the track. Note that this meta-event is simply a description; MIDI synthesisers are
not required (and rarely if ever) respond to it. This meta-event is particularly useful in
sequences prepared for synthesisers which do not conform to the General MIDI patch set, as it
documents the intended instrument for the track when the sequence is used on a synthesiser with a
different patch set.
Track, Time, Marker_t, "Text"
The Text marks a point in the sequence which occurs at the given Time, for example
"Third Movement".
Track, Time, Cue_point_t, "Text"
The Text identifies synchronisation point which occurs at the specified Time, for example,
"Door slams".
Track, Time, Lyric_t, "Text"
The Text gives a lyric intended to be sung at the given Time. Lyrics are often broken down into
separate syllables to time-align them more precisely with the sequence.
Track, Time, Text_t, "Text"
This meta-event supplies an arbitrary Text string tagged to the Track and Time. It can be used
for textual information which doesn't fall into one of the more specific categories given above.
Track, 0, Sequence_number, Number
This meta-event specifies a sequence Number between 0 and 65535, used to arrange multiple tracks
in a type 2 MIDI file, or to identify the sequence in which a collection of type 0 or 1 MIDI files
should be played. The Sequence_number meta-event should occur at Time zero, at the start of the
track.
Track, Time, MIDI_port, Number
This meta-event specifies that subsequent events in the Track should be sent to MIDI port (bus)
Number, between 0 and 255. This meta-event usually appears at the start of a track with Time
zero, but may appear within a track should the need arise to change the port while the track is
being played.
Track, Time, Channel_prefix, Number
This meta-event specifies the MIDI channel that subsequent meta-events and System_exclusive events
pertain to. The channel Number specifies a MIDI channel from 0 to 15. In fact, the Number may be
as large as 255, but the consequences of specifying a channel number greater than 15 are
undefined.
Track, Time, Time_signature, Num, Denom, Click, NotesQ
The time signature, metronome click rate, and number of 32nd notes per MIDI quarter note (24 MIDI
clock times) are given by the numeric arguments. Num gives the numerator of the time signature as
specified on sheet music. Denom specifies the denominator as a negative power of two, for example
2 for a quarter note, 3 for an eighth note, etc. Click gives the number of MIDI clocks per
metronome click, and NotesQ the number of 32nd notes in the nominal MIDI quarter note time of 24
clocks (8 for the default MIDI quarter note definition).
Track, Time, Key_signature, Key, Major/Minor
The key signature is specified by the numeric Key value, which is 0 for the key of C, a positive
value for each sharp above C, or a negative value for each flat below C, thus in the inclusive
range -7 to 7. The Major/Minor field is a quoted string which will be "major" for a major key and
"minor" for a minor key.
Track, Time, Tempo, Number
The tempo is specified as the Number of microseconds per quarter note, between 1 and 16777215. A
value of 500000 corresponds to 120 quarter notes ("beats") per minute. To convert beats per
minute to a Tempo value, take the quotient from dividing 60,000,000 by the beats per minute.
Track, 0, SMPTE_offset, Hour, Minute, Second, Frame, FracFrame
This meta-event, which must occur with a zero Time at the start of a track, specifies the SMPTE
time code at which it should start playing. The FracFrame field gives the fractional frame time
(0 to 99).
Track, Time, Sequencer_specific, Length, Data, ...
The Sequencer_specific meta-event is used to store vendor-proprietary data in a MIDI file. The
Length can be any value between 0 and 2**28-1, specifying the number of Data bytes (between 0 and
255) which follow. Sequencer_specific records may be very long; programs which process MIDI CSV
files should be careful to protect against buffer overflows and truncation of these records.
Track, Time, Unknown_meta_event, Type, Length, Data, ...
If midicsv encounters a meta-event with a code not defined by the standard MIDI file
specification, it outputs an unknown meta-event record in which Type gives the numeric meta-event
type code, Length the number of data bytes in the meta-event, which can be any value between 0 and
2**28-1, followed by the Data bytes. Since meta-events include their own length, it is possible
to parse them even if their type and meaning are unknown. csvmidi will reconstruct unknown meta-
events with the same type code and content as in the original MIDI file.
Channel Events
These events are the ``meat and potatoes'' of MIDI files: the actual notes and modifiers that command the
instruments to play the music. Each has a MIDI channel number as its first argument, followed by event-
specific parameters. To permit programs which process CSV files to easily distinguish them from meta-
events, names of channel events all have a suffix of ``_c''.
Track, Time, Note_on_c, Channel, Note, Velocity
Send a command to play the specified Note (Middle C is defined as Note number 60; all other notes
are relative in the MIDI specification, but most instruments conform to the well-tempered scale)
on the given Channel with Velocity (0 to 127). A Note_on_c event with Velocity zero is equivalent
to a Note_off_c.
Track, Time, Note_off_c, Channel, Note, Velocity
Stop playing the specified Note on the given Channel. The Velocity should be zero, but you never
know what you'll find in a MIDI file.
Track, Time, Pitch_bend_c, Channel, Value
Send a pitch bend command of the specified Value to the given Channel. The pitch bend Value is a
14 bit unsigned integer and hence must be in the inclusive range from 0 to 16383.
Track, Time, Control_c, Channel, Control_num, Value
Set the controller Control_num on the given Channel to the specified Value. Control_num and Value
must be in the inclusive range 0 to 127. The assignment of Control_num values to effects differs
from instrument to instrument. The General MIDI specification defines the meaning of controllers
1 (modulation), 7 (volume), 10 (pan), 11 (expression), and 64 (sustain), but not all instruments
and patches respond to these controllers. Instruments which support those capabilities usually
assign reverberation to controller 91 and chorus to controller 93.
Track, Time, Program_c, Channel, Program_num
Switch the specified Channel to program (patch) Program_num, which must be between 0 and 127. The
program or patch selects which instrument and associated settings that channel will emulate. The
General MIDI specification provides a standard set of instruments, but synthesisers are free to
implement other sets of instruments and many permit the user to create custom patches and assign
them to program numbers.
Apparently due to instrument manufacturers' skepticism about musicians' ability to cope with the
number zero, many instruments number patches from 1 to 128 rather than the 0 to 127 used within
MIDI files. When interpreting Program_num values, note that they may be one less than the patch
numbers given in an instrument's documentation.
Track, Time, Channel_aftertouch_c, Channel, Value
When a key is held down after being pressed, some synthesisers send the pressure, repeatedly if it
varies, until the key is released, but do not distinguish pressure on different keys played
simultaneously and held down. This is referred to as ``monophonic'' or ``channel'' aftertouch
(the latter indicating it applies to the Channel as a whole, not individual note numbers on that
channel). The pressure Value (0 to 127) is typically taken to apply to the last note played, but
instruments are not guaranteed to behave in this manner.
Track, Time, Poly_aftertouch_c, Channel, Note, Value
Polyphonic synthesisers (those capable of playing multiple notes simultaneously on a single
channel), often provide independent aftertouch for each note. This event specifies the aftertouch
pressure Value (0 to 127) for the specified Note on the given Channel.
System Exclusive Events
System Exclusive events permit storing vendor-specific information to be transmitted to that vendor's
products.
Track, Time, System_exclusive, Length, Data, ...
The Length bytes of Data (0 to 255) are sent at the specified Time to the MIDI channel defined by
the most recent Channel_prefix event on the Track, as a System Exclusive message. Note that
Length can be any value between 0 and 2**28-1. Programs which process MIDI CSV files should be
careful to protect against buffer overflows and truncation of these records.
Track, Time, System_exclusive_packet, Length, Data, ...
The Length bytes of Data (0 to 255) are sent at the specified Time to the MIDI channel defined by
the most recent Channel_prefix event on the Track. The Data bytes are simply blasted out to the
MIDI bus without any prefix. This message is used by MIDI devices which break up long system
exclusive message into small packets, spaced out in time to avoid overdriving their modest
microcontrollers. Note that Length can be any value between 0 and 2**28-1. Programs which
process MIDI CSV files should be careful to protect against buffer overflows and truncation of
these records.
EXAMPLES
The following CSV file defines the five-note motif from the film Close Encounters of the Third Kind using
an organ patch from the General MIDI instrument set. When processed by midicsv and sent to a synthesiser
which conforms to General MIDI, the sequence will be played.
0, 0, Header, 1, 2, 480
1, 0, Start_track
1, 0, Title_t, "Close Encounters"
1, 0, Text_t, "Sample for MIDIcsv Distribution"
1, 0, Copyright_t, "This file is in the public domain"
1, 0, Time_signature, 4, 2, 24, 8
1, 0, Tempo, 500000
1, 0, End_track
2, 0, Start_track
2, 0, Instrument_name_t, "Church Organ"
2, 0, Program_c, 1, 19
2, 0, Note_on_c, 1, 79, 81
2, 960, Note_off_c, 1, 79, 0
2, 960, Note_on_c, 1, 81, 81
2, 1920, Note_off_c, 1, 81, 0
2, 1920, Note_on_c, 1, 77, 81
2, 2880, Note_off_c, 1, 77, 0
2, 2880, Note_on_c, 1, 65, 81
2, 3840, Note_off_c, 1, 65, 0
2, 3840, Note_on_c, 1, 72, 81
2, 4800, Note_off_c, 1, 72, 0
2, 4800, End_track
0, 0, End_of_file
BUGS
The CSV representation of a MIDI file is simply a text-oriented encoding of its contents. If the input
to midicsv contains errors which violate the MIDI standard, the resulting CSV file will faithfully
replicate these errors. Similarly, the CSV input to csvmidi must not only consist of records which
conform to the syntax given in this document, the input as a whole must also be a semantically correct
MIDI file. Programs which wish to use csvmidi to generate MIDI files from scratch should be careful to
conform to the structure required of MIDI files. When in doubt, use midicsv to dump a sequence
comparable to the one your program will create and use its structure as a template for your own.
Please report errors to bugs@fourmilab.ch.
SEE ALSO
csvmidi(1), midicsv(1)
AUTHOR
John Walker
http://www.fourmilab.ch/
This software is in the public domain. Permission to use, copy, modify, and distribute this software and
its documentation for any purpose and without fee is hereby granted, without any conditions or
restrictions. This software is provided ``as is'' without express or implied warranty.