NAME

       midistats - program to summarize the statistical properties of a midi file

SYNOPSIS

       midistats infile

DESCRIPTION

       midistats  analyzes  the  contents  of a midi file and outputs key information and various
       statistical measures. Each line of output starts with the name of the variable or variable
       array  and  the  associated  values.  The  output  is  interpreted  by  the user interface
       midiexplorer.tcl. Both programs are still being improved. Here is an explanation  of  some
       of the output.

       ntrks indicates the number of tracks in the midi file.

       ppqn the number of midi pulses per quarter note.

       keysig the key signature, followed by a major/minor flag,  the number of sharps (positive)
       or flats (negative) in the key, and the beat number where the key signature was found.

       trk is followed by the track number for which the following information applies.

       program is followed by the channel number and the General Midi Program number.

       trkinfo is an array of 8 numbers which indicates the statistical properties of  the  track
       of  interest.  The following data is given: the channel number, the first program assigned
       to this channel, the number of notes for this channel counting any chords as one note, the
       total  number  of notes for this for this channel, the sum of the MIDI pitches for all the
       notes, the sum of the note durations in MIDI pulse units, the number of control  parameter
       messages, the number of pressure messages.  and the number of distinct rhythm patterns for
       each channel

       After processing all the individual tracks,  the  following  information  applies  to  the
       entire midi file.

       npulses is the length of the longest midi track in midi pulse units

       tempocmds specifies the number of times the tempo is changed in this file.

       pitchbends specifies the total number of pitchbends in this file.

       progs is a list of all the midi programs addressed

       progsact  the amount of activity for each of the above midi programs.  The activity is the
       sum of the note durations in midi pulse units.

       progcolor: is a 17 dimensional vector where each component maps into a specific  group  of
       MIDI  programs.  Some  of  these groups are, keyboard instruments, brass instruments, wind
       instruments, and etc. More information can be found in the midiexplorer documentation.

       drums is a list of all the percussion instruments (channel 9) that were used.

       drumhits indicates the number of notes for each of the above percussion instruments.

       pitches is a histogram for the 11 pitch classes (C, C#, D ...B) that  occur  in  the  midi
       file.

       pitchact is a similar histogram but is weighted by the length of the notes.

       quietTime  is used to compute the track/channel spread in midiexplorer.  It is computed by
       summing up all the midi pulses which occur in gaps greater than 8 beats.

       totalrhythmpatterns is the total number of bar rhythm patterns for all channels except the
       percussion channel.

       collisions.  Midistats  counts the bar rhythm patterns using a hashing function. Presently
       collisions are ignored so occasionally two distinct rhythm patterns are counted as one.

Advance Percussion Analysis Tools

       A number  of  experimental  tools  for  analyzing  the  percussion  channel  (track)  were
       introduced  into  midistats  and  are accessible through the runtime arguments. When these
       tools are used in a script which runs through a collection of midi files, you can build  a
       database  of  percussion  descriptors.  Some  more details are given in the file drums.txt
       which comes with this documentation.

AUTHOR

       Seymour Shlien <fy733@ncf.ca>

                                         9 December 2022                             MIDISTATS(1)