semits -- translate selected Humdrum pitch-related representations to numerical semitones


semits [-p n] [-tx] [inputfile ...] [ > outputfile.sem]


The semits command transforms various pitch-related inputs to corresponding numerical semitone values. It outputs one or more Humdrum **semits spines containing values corresponding to the semitone distance from middle C for pitch-related input tokens. Pitches above middle C produce positive output values, whereas pitches below middle C produce negative output values. For example, the **pitch token "C3" is transformed to -12 (-ts).

The semits command is able to translate any of the pitch-related representations listed below. In each case, a tuning standard of A4 equals 440 hertz is assumed. For descriptions of the various input representations (including **semits) refer to Section 2 (Representation Reference) of this reference manual.

It is recommended that output files produced using the semits command should be given names with the distinguishing `.sem' extension.

**centshundredths of a semitone with respect to middle C=0 (e.g. 1200 equals C5)
**freqfundamental frequency (in hertz)
**fretfretted-instrument pitch tablature
**kerncore pitch/duration representation
**MIDIMusic Instrument Digital Interface tablature
**pitchAmerican National Standards Institute pitch notation (e.g. "A#4")
**semitsequal-tempered semitones with respect to middle C=0
**solfgFrench solfège system (fixed `doh')
**specCspectral centroid (in hertz)
**TonhGerman pitch system
Input representations processed by semits.


The semits command provides the following options:

-hdisplays a help screen summarizing the command syntax
-p noutput precision of n decimal places
-tsuppresses printing of all but the first note of a group of tied **kern notes
-xsuppresses printing of non-semits data
Options are specified in the command line.

The -p option can be used to set the precision of the output values to n decimal places. The default precision is integer values only. Note that semits is able to process **semits as input; this feature allows the user to round-off existing **semits data to a specified precision.

The -t ensures that only a single output value is given for tied **kern notes; the output coincides with the first note of the tie.

In the default operation, semits outputs non-pitch-related signifiers in addition to the semits value. For example, the **pitch token "A5zzz" will result in the output "21zzz" -- that is, after translating A5 to 21 semits, the "zzz" signifiers are retained in the output. For some applications, echoing non-pitch-related signifiers in the output is useful. However, in other situations, the result can prove confusing -- especially, when the non-pitch-related signifiers are numbers. Consider the case of the **kern token "8aa"; after translating `aa' to 21 semits, the non-pitch-related signifier `8' will also be output, hence the value 821 -- which will undoubtedly cause confusion. The -x option is useful for eliminating non-pitch-related signifiers from the output. For most **kern inputs, the -x option is recommended.


The following example illustrates the use of semits. The input contains six pitch-related spines -- two of which (**deg and **cocho) cannot be processed by semits. In addition, there are two non-pitch-related spines (**embell and **metpos).
!! `semits' example.
4a-]D4/48/ /52/128.11C3ct
.D4 F4/-52/237.33 6.4C3 Es3ct
rG4.r1rH2 D3.
Executing the command

semits -tx input > output

produces the following result:

!! `semits' example.
.2-12 -8128.11-12ct
.2 5.237.33 6.4-12 -9ct
r7.r1r-13 -10.
Both processed and unprocessed spines are output. Notice that the tied note at the beginning of measure 2 in the **kern spine has been rendered as a single note rather than as two notes (due to the -t option). Also notice that the non-pitch-related signifiers (e.g. foo) in the first notes of the **pitch, **MIDI, and **cocho spines have been stripped away (due to the -x option).


The file x_option.awk is used by this program when the -x option is invoked.


DOS 2.0 and up, with the MKS Toolkit. OS/2 with the MKS Toolkit. UNIX systems supporting the Korn shell or Bourne shell command interpreters, and revised awk (1985).


**cents (2), cents (4), **freq (2), freq (4), **fret (2), **kern (2), kern (4), **MIDI (2), midi (4), **pitch (2), pitch (4), **semits (2), **solfg (2), solfg (4), **specC (2) specC (4), **Tonh (2), tonh (4)