1. Digital Koto Music Scores
Forum on Information Technology (FIT) 2002
IPSJ & IEICE; Tokyo Institute of Technology
Craig Sapp
Stanford University
Sachiko Deguchi
Kogyokusha College of Technology

2. Purpose Develop computer printing system for koto music
Arabic numeral notation for Western students of koto.
Typeset new compositions for koto music.
Convert Western music notation into koto notation.
Create digital encoding format for koto scores.
Electronic database of koto music.
Analysis of koto music.

3. The Koto
String 1
Performer
sits here
String 13

4. Existing Typeset Koto Music
Yamada school engraved music:
Ikuta school
engraved music:
Our computer-typeset music:

5. Computer Typesetting Process
A: Ideally spaced music with spacing boxes visible.
Only music elements with controlling widths.
Spacing ratio of 0.65 for duration ratio of 1:2.
B: Spacers scaled to fit music in margins.
Box widths all scaled by the same amount.
Widths of music elements not scaled.
C: Vertical elements added.
Add ornaments (e.g.: hiki), fingerings, rhythmic beaming
Final score output is in PostScript format
vector graphics (scalable)
convertible to PDF format

6. Koto Notation Encoding Problems
Most computer music application written for standard Western notation.
Standard Western notation does not map well to koto score
many glissando techniques in koto music.
standard koto tunings contain same pitch on strings 1 + 5
strings of koto can be re-tuned
difficult to remember new pitch/string mappings

7. Symbolic Encoding Format
koto2eps
**koto
*M4/4
*tune[d:G:A:A#:d:d#:g:a:a#:dd:dd#:gg:aa]
{5+i - 3 1s =2 0}
{3|sb
3|sc
8|.
7|| 6|
7|o =3 1c
5|.
4|| 3}
{1s =4 9 8| 7| *-
Based on the Humdrum File Format for music research:
10, 11, 12, 13
Pitch:
String numbers from A, B, C, D
Rests: number 0
Rhythm:
One beat by default
| symbol halves duration (Western beams)
- symbol for ornamentation placement
Other:
= barlines
{,} phrase markings
a, b, c fingerings
i, s, o ornaments

8. Web Interface for Creating Scores

9. Koto Notation to Western Notation
*M4/4
*tune[d:G:A:A#:d:d#:g:a:a#:dd:dd#:gg:aa]
{5+i - 3 1s =2 0}
{3|sb
3|sc
8|.
7|| 6|
7|o . =3
**kern
*M4/4
{2d . 4A
4d: 4G: =2
4r}
{8A: 8A#:
8A: 8A#:
8.a
16g
8d#
16gH
16ah =3
Automatic conversion from koto data to Humdrum kern data
Kern data can then be typeset
kern mup
kern MusicXML
MusicXML Finale

10. Western Notation to Koto Notation
Program written to convert western notated music into koto performance notation.
E mode
G mode
Tuning:
c:d:e:f:g:a:b:cc:dd:ee:ff:gg:aa

11. Electronic Data Conversion Paths
Humdrum Koto
koto2eps
Analysis
koto2kern
kern2koto
paper ms
Humdrum Kern
Mup
Performance
modeling
krn2xml
smf
MIDI
MusicXML
dolet
Finale
sound

12. Further information Website for koto scores: http://koto.sapp.org
Humdrum koto data format specification:
Koto score generating web interface: