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diff --git a/upstream/debian-unstable/man1/midistats.1 b/upstream/debian-unstable/man1/midistats.1 new file mode 100644 index 00000000..6b9c5d44 --- /dev/null +++ b/upstream/debian-unstable/man1/midistats.1 @@ -0,0 +1,323 @@ +.TH MIDISTATS 1 "11 February 2024" +.SH NAME +\fBmidistats\fP \- program to summarize the statistical properties of a midi file +.SH SYNOPSIS +midistats \fIinfile\fP + +.SH DESCRIPTION +\fImidistats\fP 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. +.PP +ntrks indicates the number of tracks in the midi file. +.PP +ppqn the number of midi pulses per quarter note. +.PP +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. +.PP +trk is followed by the track number for which the following information +applies. +.PP +program is followed by the channel number and the General Midi Program +number. +.PP +trkinfo is an array of 19 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. +the number of distinct rhythm patterns for each channel +the number of pulses the channel was inactive +the minimum pitch value +the maximum pitch value +the minimum note length in pulses +the maximum note length in pulses +the number of gaps in the channel +the entropy of the pitch class histogram for that channel +the number of notes whose pitch were the same as the previous note +the number of notes whose pitch changed by less than 4 semitones +the number of notes whose pitch changed by 4 or more semitones +(In event of a chords the maximum pitches are compared.) +.PP +After processing all the individual tracks, the following information +applies to the entire midi file. +.PP +npulses is the length of the longest midi track in midi pulse units +.PP +tempocmds specifies the number of times the tempo is changed in this +file. +.PP +pitchbends specifies the total number of pitchbends in this file. +.PP +pitchbendin c n specifies the number of pitchbends n in channel c +.PP +progs is a list of all the midi programs addressed +.PP +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. +.PP +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. +.PP +drums is a list of all the percussion instruments (channel 9) that were +used. +.PP +drumhits indicates the number of notes for each of the above percussion +instruments. +.PP +pitches is a histogram for the 11 pitch classes (C, C#, D ...B) +that occur in the midi file. +.PP +key indicates the key of the music, the number of sharps (positive) or +flats (negative) in the key signature, and a measure of the confidence +in this key signature. The key was estimated from the above pitch histogram +by convolving with Craig Sapp's model. The peak of rmaj or rmin (below) +indicates the key. A correlation less than 0.4 indicates that the pitch +histogram does not follow the histogram of a major or minor scale. +(It may be the result of a mixture of two key signatures.) +.PP +rmaj the cross correlation coefficients with Craig Sapp's major key model +for each of the 11 keys (C, C#, D, ...,B). +.PP +rmaj the cross correlation coefficients with Craig Sapp's minor key model +for each of the 11 keys (C, C#, D, ...,B). +.PP +pitchact is a similar histogram but is weighted by the length of +the notes. +.PP +chanvol indicates the value of the control volume commands in the +midi file for each of the 16 channels. The maximum value is 127. +It scales the loudness of the notes (velocity) by its value. +.PP +chnact returns the amount of note activity in each channel. +.PP +trkact returns the number of notes in each track. +.PP +totalrhythmpatterns is the total number of bar rhythm patterns for +all channels except the percussion channel. +.PP +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. +.PP +Midistats prints a number of arrays which may be useful in +determining where the music in the track is a melody line or +chordal rhythmic support. These arrays indicate the properties +for each of the 16 channels. (The percussion channel 9 contains +zeros.) In the case same channel occurs in several tracks, these +numbers are the totals for all track containing that channel. +Here is a description of these properties. +.PP +nnotes: the total number of notes in each channel +.br +nzeros: the number of notes whose previous note was the same pitch +.br +nsteps: the number of notes whose pitch difference with the previous +note was less than 4 semitones. +.br +njumps: the number of notes whose pitch difference with the previous +note was 4 or more semitones. +.br +rpats: the number of rhythmpatterns for each channels. This is a +duplication of data printed previously. +.br +pavg: the average pitch of all the notes for each channel. +.PP +In addition the midistats may return other codes that describe +other characteristics. They include + +unquantized - the note onsets are not quantized +.br +triplets - 3 notes played in the time of 2 notes are present +.br +qnotes - the rhythm is basically simple +.br +clean_quantization - the note onsets are quantized into 1/4, 1/8, 1/16 time units. +.br +dithered_quantization - small variations in the quantized note onsets. +.br +Lyrics - lyrics are present in the meta data +.br +programcmd - there may be multiple program changes in a midi channel + + + +.SH Advanced Percussion Analysis Tools + +.PP +The MIDI file devotes channel 9 to the percussion instruments +and over 60 percussion instruments are defined in the MIDI +standard. Though there is a lot of diversity in the percussion +track, for most MIDI files only the first 10 or so percussion +instruments are important in defining the character of the track. The +program Midiexplorer has various tools for exposing the percussion +channel which are described in the documentation. The goal +here is to find the essential characteristics of the percussion +track which distinguishes the MIDI files. This is attempted +in the program midistats. Here is a short description. + + +.br + +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. + +.SH OPTIONS +.PP +-corestats +.br +outputs a line with 5 numbers separated by tabs. eg +.br +1 8 384 4057 375 +.br +It returns the number of tracks, the number of channels, the +number of divisions per quarter note beat (ppqn), +the number of note onsets in the midi file, and the maximum +number of quarter note beats in midi file. + + +.PP +-pulseanalysis +.br +counts the number of note onsets as a function of its onset time +relative to a beat, grouping them into 12 intervals and returns +the result as a discrete probability density function. Generally, +the distribution consists of a couple of peaks corresponding +to quarter notes or eigth notes. If the distribution is flat, +it indicates that the times of the note occurrences have not been +quantized into beats and fractions. Here is a sample output. +.br +0.349,0.000,0.000,0.160,0.000,0.000,0.298,0.000,0.000,0.191,0.000,0.000 + +.PP +-panal +.br +Counts the number of note onsets for each percussion instrument. The first +number is the code (pitch) of the instrument, the second number is the +number of occurrences. eg. +.br +35 337 37 16 38 432 39 208 40 231 42 1088 46 384 49 42 54 1104 57 5 70 1040 85 16 + +.PP +-ppatfor n +.br +where n is the code number of the percussion instrument. Each beat +is represented by a 4 bit number where the position of the on-bit +indicates the time in the beat when the drum onset occurs. The bits +are ordered from left to right (higher order bits to lower order +bits). This is the order of bits that you would expect in a +time series. +Thus 0 indicates that there was no note onset in that beat, 1 indicates +a note onset at the end of the beat, 4 indicates a note onset +in the middle of the beat, and etc. The function returns a string +of numbers ranging from 0 to 7 indicating the presence of note onsets +for the selected percussion instrument for the sequence of beats +in the midi file. Here is a truncated sample of the output. +.br + +0 0 0 0 0 0 0 0 1 0 0 4 1 0 0 4 1 0 0 4 1 0 0 4 1 0 0 4 1 0 0 4 1 4 4 0 +1 0 0 0 1 0 5 0 1 0 5 0 1 0 5 0 1 0 5 0 1 0 5 0 1 0 5 0 1 0 5 0 1 0 0 0 +1 0 5 0 1 0 5 0 1 etc. + +.br +One can see a repeating 4 beat pattern. + +.PP +-ppat +.br +midistats attempts to find two percussion instruments in the midi file +which come closest to acting as the bass drum and snare drum. +If it is unsuccessful, it returns a message of its failue. Otherwise, +encodes the position of these drum onsets in a 8 bit byte for each +quarter note beat in the midi file. The lower (right) 4 bits encode the +bass drum and the higher (left) 4 bits encode the snare drum in the +same manner as described above for -ppatfor. +.br +0 0 0 0 0 0 0 0 0 0 33 145 33 145 33 145 33 145 33 145 33 145 33 145 +.br +33 145 33 145 33 145 33 145 33 145 33 145 33 145 33 145 33 145 33 145 +.br +33 145 33 145 33 145 33 145 33 145 33 and etc. + + +.PP +-ppathist +.br +computes and displays the histogram of the values that would appear +when running the -ppat. eg. +.br +bass 35 337 +.br +snare 38 432 +.br +1 (0.1) 64 32 (2.0) 8 33 (2.1) 136 144 (9.0) 8 145 (9.1) 136 +.br +The bass percussion code, the number of onsets, and the snare +percussion code and the number of onsets are given in the +first two lines. In the next line the number of occurrences of +each value in the -ppat listing is given. The number in parentheses +splits the two 4-bit values with a period. Thus 33 = (2*16 + 1). + +.PP +-pitchclass +.br +Returns the pitch class distribution for the entire midi file. + +.PP +-nseqfor n +.br +Note sequence for channel n. This option produces a string of bytes +indicating the presence of a note in a time unit corresponding to +an eigth note. Thus each quarter note beat is represented by two +bytes. The pitch class is represented by the line number on the +staff, where 0 is C. Thus the notes on a scale are represented +by 7 numbers, and sharps and flats are ignored. The line number is +then converted to a bit position in the byte, so that the pitch +classes are represented by the numbers 1,2,4,8, and etc. A chord +of consisting of two note onsets would set two of the corresponding +bits. If we were to represent the full chromatic scale consisting +of 12 pitches, then we would require two-byte integers or +twice of much memory. +.br +Though the pitch resolution is not sufficient to distinguish +major or minor chords, it should be sufficient to be identify some +repeating patterns. +.PP +-nseq +.br +Same as above except it is applied to all channels except the +percussion channel. +.br +.PP +-nseqtokens +Returns the number of distinct sequence elements for each channel. +The channel number and number of distinct elements separated by +a comma is returned in a tab separated list for all active channels +except the percussion channel. Here is an example. +.br +2,3 3,4 4,11 5,6 6,3 7,3 8,6 9,3 11,2 12,1 +.br + +-ver (version number) + + +.SH AUTHOR +Seymour Shlien <fy733@ncf.ca> + + + |