JEIDA Standard of Symbols for
Japanese Text-to-Speech Synthesizers
TANAKA Kazuyo1, AKABANE Makoto2,
MINOWA Toshimitsu3, ITAHASHI Shuichi4
1 Electrotechnical
Laboratory, 1-1-4 Umezono, Tsukuba, 305-8568, Japan. ktanaka@etl.go.jp
SONY Corporation, 2-15-3 Konan Minato-ku, Tokyo, 108-6201, Japan. akabane@pdp.crl.sony.co.jp
3
Matsusita Communication Ind. Co., Ltd., Yokohama, 224-8539, Japan. minowa@adl.mci.mei.co.jp
4
University of Tsukuba, 1-1-1 Tennodai, Tsukuba, 305-8573, Japan. itahashi@milab.is.tsukuba.ac.jp
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symbol system with several examples and comments.
In “JEIDA-62-2000” version, the JEIDA
Committee determined the symbols and description
format that every TTS engine needs to accept as its
input, that is, the TTS engine synthesizes speech by
reading such a character sequence as is written by the
standardized symbols and description format.
Through the discussion in the Committee, we have
considered that the symbols should have the
following characterization:
(1) they do not depend upon any specific
applications nor platforms, such as hardware
architectures, operating systems, programming
languages, character codes, etc. , and also
(2) they should have availability for wide
applications.
ABSTRACT
This paper presents a standard of symbols
commonly used for Japanese text-to-speech
synthesizers. The standard has been discussed in
the Speech Input/Output Systems Expert
Committee of the Japan Electronic Industry
Development Association (JEIDA), and was
announced from the JEIDA as the JEIDA Standard
named “JEIDA-62-2000” in March 2000.
We
describe here its basic policy and outline of the
symbol system with several examples.
1. INTRODUCTION
Recently, text-to-speech (TTS) synthesizers have
rapidly spread to various applications and/or services
in our life. Japanese makers thus put many TTS
engines on the market. These TTS engines, however,
employ individual (machine-dependent) interfaces
and symbol systems, so that it becomes a serious
obstacle when users implement application systems
that incorporate any of the TTS engines. To help to
resolve such a problem, the JEIDA Committee began,
in 1995, to discuss standardization of symbols and
input format used for TTS engines and, in March
2000, brought it to the first concluding version as the
JEIDA Standard, “JEIDA-62-2000”[1]. At the same
time, the JEIDA Committee also presented guidelines
for speech synthesis system performance evaluation
as “JEIDA Guideline” in this March[2]. In the
following sections, we describe the outline of the
2. CLASSIFICATION OF THE
SYMBOLS
First of all, to make clear the characteristics of
the symbols for TTS synthesizers, we classified this
kind of symbols into categories shown in Table 1,
where the vertical indicates level of description and
the horizontal means features conveyed by the
symbols. More specifically, it is shown in Fig. 1,
which indicates the configuration of each symbol
category in relation to TTS systems and shows typical
text format examples.
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Table 1: Classification of the Symbols for Japanese TTS Synthesizers
Level
Pronunciation feature
Prosodic feature
Control tag
Text-level
----Kana-level
Kana-level representation
Text-embedded tags
Pronunciation symbols
Prosodic symbols
Allophone-level
Allophone-level representation
Pronunciation symbols
Prosodic symbols
Input Text
Japanese Text Analysis
Text-level representation:
<PRON SYM=”キョ’－”>今日</PRON>は天気
がよい。
Kana-level representation:
(Kana) キョウ’ ワ|_テンキカ゜/ヨ’ イ.
(Alphabetic) kyo’-wa|_te’nnkinga/yo’i.
Allophone-level Analysis
Allophone-level representation:
(SAMPA) kjo!:wa||te!NkiNa|jo!i
Synthesizer
Engine
Fig.1 JEIDA Symbols in relation to a TTS system.
character sets for the representation symbols.
Thus, the monosyllables are written by 1) a single
Kana-character or character string (e.g. キョー), or
2) an alphabetic-character or character string (e.g.
kyo-), as indicated in the Kana-level representation
shown in Fig. 1.
While these character
representations are uniquely defined, their coding
methods are not specified here to be independent
of application platforms.
The representation
method does not meet with the Japanese
orthographical transcription in several points. No
characters are prepared for devocalizations of
vowels because they are usually predictable from
the phonetic contexts.
On the other hand,
nazalization of /g/, which is phonetically distinct
but not recognized as a phonemic unit in the
Japanese language, is explicitly defined by a
3. KANA-LEVEL REPRESENTATION
3.1 Pronunciation symbols
The Kana-level Representation is used in a
stage where a basic pronunciation of a word
sequence is given based on a result of text analysis.
Input Japanese texts are usually written with
Chinese characters, Hira-kana and Kata-kana
characters, Arabic numerals, etc, so that these texts
need to be transformed to pronunciation symbol
sequences using the text analysis result. The
pronunciation symbols here represent a phonetic
aspect of words except their prosodic features, and
are uniquely defined for every Japanese
monosyllable (see Appendix-I). In Japan, the
pronunciation is usually written by Kana or
alphabetic characters, so that we accepted both
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5. TEXT-EMBEDDED
CONTROL-TAGS
different character, because this type of phonetic
alteration is derived from the text analysis result.
The Text-Embedded Control-Tags are defined
to specify a kind of language, speaking rate,
volume level of speech, part of speech, etc.,
included in the input text, for examples, and are
written by XML format. We determined them by
referring to several documents already announced,
such as Microsoft Speech API (SAPI) [7] and the
Aural Style Sheet of W3C (World Wide Web
Consortium) [8]. At the same time we also
considered the characteristics of the Japanese
language and TTS engines for Japanese. Thus,
most of such Control-Tags as overlapped and
already defined in the SAPI were adopted in the
JEIDA Standards, but several tags were added as
components specifically used for Japanese TTS
synthesizers.
3.2 Prosodic symbols
The prosodic symbols here are defined for
those prosodic features as accent position, accent
phrase boundary, phrase boundary, sentence period
and its intonation types (eg., normal, interrogative,
or exclamatory), and pause insertion, contained in
Japanese texts (see Appendix II). They are
defined on the assumption that they are able to
represent Tokyo dialect. We did not determine
such symbols as representing fine prosodic
phenomena, because it might be troublesome in
implementing various applications.
Several
closer definitions are given in the Allophone-level
Representation.
4. ALLOPHONE-LEVEL
REPRESENTATION
5.1 Examples
of
Control-Tags
Allophone-level Representation is determined
for specifying more details of pronunciations. It
is based on IPA representation of Japanese
syllables. However, the IPA representation of
Japanese itself is still including several ambiguous
items, so that we referred to a report by Oonishi et
al [3] in determining this standard. For easy use
in computer programs, we adopted the XSAMPA
(eXtended Speech Assessment Methods Phonetic
Alphabet [5,6]) as ASCII code expression
corresponding to the IPA.
Prosodic features are also represented using
symbols defined in the suprasegmentals of IPA.
In representing the accentuation, we adopted
symbols indicating rise and fall positions(see
Appendix III), so that it is able to represent several
dialects other than Tokyo dialect. Since the IPA
does not intend to express general prosodic
characteristics, the current set of the symbols for
prosodic features is not yet enough to express
details.
We consider that the symbols for
prosodic features needs further investigations in
the future to compose a more convenient
representation.
the
Text-Embedded
The Control-Tags are categorized as those for
controlling TTS systems, indicating pronunciations,
and helping text analysis. Examples are shown in
the following.
(1) Tag examples for controlling TTS systems:
BOOKMARK: inserting a bookmark.
SPEECH: specifying a scope of the Tags
defined in this standard.
LANG: specifying a language.
VOICE: specifying a font of voice, such as
specified person’s voice tone.
RESET: resetting values in the section
corresponding to “SPEECH”.
(2) Tag examples for indicating pronunciations:
SILENCE: inserting a pause.
EMPH: indicating a emphasis phrase, word,
etc.
SPELL: indicating reading by alphabetic
character pronunciation of a word spelling.
RATE: specifying a speaking rate.
VOLUME: specifying volume of speech.
PITCH: specifying average pitch level.
(3) Tag examples for helping text analysis:
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PARTOFSP: specifying a part of speech in the
text.
CONTEXT: specifying prior information in the
scope.
REGWORD: registration of a pronunciation
and/or part of speech, etc, for a specified word.
REFERENCES
[1] Japan Electronic Industry Development
Association (JEIDA) Standard: Standard of
symbols
for
Japanese
text-to-speech
synthesizer (in Japanese), JEIDA-62-2000
(March, 2000).
[2] JEIDA: Guidelines for speech synthesis
system performance evaluation methods (in
Japanese), JEIDA-G-2000 (March, 2000). S.
Itahashi, “Guidelines for Japanese speech
synthesizer evaluation,” Proc. LREC2000,
pp.xxx-xxx, May, 2000.
[3] M. Oonishi, S. Toki, M. Dantsuji, “Research
report on phonetic symbol representation of
Japanese,” Proceedings 1995 Meeting,
Phonetic Association of Japan, pp.11-17, 1995.
[4] Dafydd Gibbon, Roger Moore, Richard Winski,
“Handbook of Standards and Resources for
Spoken Language Systems,” Mouton de
Gruyter, 1997.
[5] SAMPA
http://www.phon.ucl.ac.uk/home/sampa/home
[6] Microsoft Speech SDK
http://research.microsoft.com/stg/
[7] W3C - http://www.w3.org/TR/WD-CSS2/
[8] Voice XML - http://www.voicexml.org/
5.2 Attributes Specification
Two ways are acceptable in specifying
attributes of the Tags, such as speaking rate, pitch
level, volume of speech, etc. One is to express by
an absolute value (or level), and the other is by
relative value (or level) in relation to the preceding
one, as shown in the following:
(1) Using the absolute value:
(The name of attribute is “AbsAttr”.)
<TagName AbsAttr=”5”> <The value is set to 5>
<TagName AbsAttr=”6”> <The value is set to 6>
</TagName> <The value is reset to 5>
</TagName > <The value is reset to one before “5”>
(2)Using the relative value:
(The name of attribute is “AbsAttr” and the
reference value of RelAttr=”0”.)
<TagName RelAttr=”+5”> <The value is set to 5>
<TagName RelAttr=”+6”> <The value is set to 11>
</TagName> <The value is reset to 5>
</TagName> <The value is reset to 0>
6. CONCLUDING REMARKS
The
JEIDA
Standard
of
Symbols
“JEIDA-62-2000” is the first version that defined
primary part of the symbol system for Japanese
TTS synthesizers. It will be revised in the future
to meet with the progress of TTS engines and/or
their application systems.
ACKNOWLEDGMENT
The authors wish to thank all the members of
the Speech Input/Output Systems Expert
Committee of JEIDA for their intensive effort and
discussion to establish this Standard of Symbols.
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Appendix-I: Kana-level Symbols for Japanese monosyllables pronunciation.
表2-1 読み記号
ア
a
カ
ka
サ
sa
タ
ta
ナ
na
ハ
ha
マ
ma
ラ
ra
ガ
ga
ザ
za
ダ
da
バ
ba
パ
pa
ヴァ
va
カ゜
nga
ン
nn
イ
i
キ
ki
シ
shi
チ
chi
ニ
ni
ヒ
hi
ミ
mi
リ
ri
ギ
gi
ジ
ji
ディ
di
ビ
bi
ピ
pi
ティ
ti
ヴィ
vi
キ゜
ngi
スィ
si
ズィ
zi
ッ
q
ウ
u
ク
ku
ス
su
ツ
t su
ヌ
nu
フ
hu
ム
mu
ル
ru
グ
gu
ズ
zu
ドゥ
du
ブ
bu
プ
pu
ト ゥ
tu
ヴ
vu
ク゜
ngu
エ
e
ケ
ke
セ
se
テ
te
ネ
ne
ヘ
he
メ
me
レ
re
ゲ
ge
ゼ
ze
デ
de
ベ
be
ペ
pe
オ
o
コ
ko
ソ
so
ト
to
ノ
no
ホ
ho
モ
mo
ロ
ro
ゴ
go
ゾ
zo
ド
do
ボ
bo
ポ
po
ヤ
ユ
ya
yu
キャ
キュ
kya
kyu
シャ
シュ
sha
shu
チャ
チュ
cha
chu
ニャ
ニュ
nya
nyu
ヒャ
ヒュ
hya
hyu
ミャ
ミュ
mya
myu
リャ
リュ
r ya
r yu
ギャ
ギュ
gya
gyu
ジャ
ジュ
ja
ju
デャ
デュ
dya
dyu
ビャ
ビュ
bya
byu
ピャ
ピュ
pya
pyu
テャ
テュ
t ya
t yu
ヴェ ヴォ ヴャ
ヴュ
ve
vo
vya
vyu
ケ゜ コ ゜ キ゜ ャ キ゜ ュ
nge ngo
ngya ngyu
フャ
フュ
f ya
f yu
イェ
ヨ
ye
yo
キェ
キョ
kye
kyo
シェ
ショ
she
sho
チェ
チョ
che
cho
ニェ
ニョ
nye
nyo
ヒェ
ヒョ
hye
hyo
ミェ
ミョ
mye
myo
リェ
リョ
r ye
r yo
ギェ
ギョ
gye
gyo
ジェ
ジョ
je
jo
ディ ェ デョ
dye
dyo
ビェ
ビョ
bye
byo
ピェ
ピョ
pye
pyo
ティ ェ テョ
t ye
t yo
ヴィ ェ ヴョ
vye
vyo
キ゜ ェ キ゜ ョ
ngye ngyo
フィ ェ フョ
f ye
f yo
ー
-
5
ワ
wa
クァ
kwa
スァ
swa
ツァ
t sa
ヌァ
nwa
ファ
fa
ムァ
mwa
ルァ
r wa
グァ
gwa
ズァ
zwa
ドゥァ
dwa
ブァ
bwa
プァ
pwa
ト ゥァ
t wa
ヴゥ ァ
vwa
ク゜ ァ
ngwa
ウィ
wi
クィ
kwi
スゥ ィ
swi
ツィ
t si
ヌィ
nwi
フィ
fi
ムィ
mwi
ルィ
r wi
グィ
gwi
ズィ
zwi
ドゥィ
dwi
ブィ
bwi
プィ
pwi
ト ゥィ
t wi
ヴゥ ィ
vwi
ク゜ ィ
ngwi
ウェ
we
クェ
kwe
スェ
swe
ツェ
t se
ヌェ
nwe
フェ
fe
ムェ
mwe
ルェ
r we
グェ
gwe
ズェ
zwe
ドゥェ
dwe
ブェ
bwe
プェ
pwe
ト ゥェ
t we
ヴゥ ェ
vwe
ク゜ ェ
ngwe
ウォ
wo
クォ
kwo
スォ
swo
ツォ
t so
ヌォ
nwo
フォ
fo
ムォ
mwo
ルォ
r wo
グォ
gwo
ズォ
zwo
ドゥォ
dwo
ブォ
bwo
プォ
pwo
ト ゥォ
t wo
ヴゥ ォ
vwo
ク゜ ォ
ngwo
Appendix-II: Kana-level Symbols for Prosodic Features.
Function
Accent position
Accent phrase boundary
Phrase boundary
End of sentence, Normal/assertive intonation
End of sentence, Interrogative intonation
End of sentence, Exclamatory intonation
1-mora pause insertion
Symbol
’
／
｜
.
？
！
＿
(The ASCII codes are represented by the decimal system.)
ASCII code
039
047
124
046
063
033
095
Appendix-III: Allophone-level Symbols for Prosodic Features.
Function
XSAMPA
ASCII code
Accent, Upstep
^
094
Accent, Downstep
!
033
Accent phrase boundary, Minor (foot) group
|
124
Phrase boundary, Major (intonation) group
||
124 124
End of sentence, Global fall
<F>
060 070 062
End of sentence, Global rise
<R>
060 082 062
1-mora pause insertion
...
046 046 046
(The IPA symbols corresponding to XSAMPA’s are omitted here.)
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