Intonation
In eSpeak NG's standard intonation model, a "tune" is applied to each clause depending on its punctuation. Other intonation models may be used for some languages, such as tone languages.
Named tunes are defined in the text file phsource/intonation. This file
must be compiled for use by eSpeak NG by using:
espeak-ng --compile-intonations
Clauses
The tunes which are used for a language can be specified by using a
tunes statement in a voice file in espeak-data/voices. e.g.:
tunes s1 c1 q1 e1
It's parameters are four tune names which are used for clauses which end in:
- Full-stop.
- Comma.
- Question mark.
- Exclamation mark.
A clause consists of the following parts:
Pre-head
These are any unstressed syllables before the first stressed syllable.
Head
This is the part from the first stressed syllable up to the last syllable before the nucleus.
Nucleus
This is stressed syllable which is the focus of the clause. eSpeak chooses the last stressed syllable of the clause.
Tail
These are the syllables after the nucleus.
Tune Definitions
Here is an example tune definition from the file phsource/intonation:
tune s1
prehead 46 57
headenv fall 16
head 4 80 55 -8 -5
headextend 0 63 38 13 0
nucleus fall 70 18 24 12
nucleus0 fall 64 8
endtune
tune
tune <tune name>
Starts the definition of a tune. The tune name can be used in a tunes
statements in voice files.
endtune
endtune <tune name>
Ends the definition of a tune.
prehead
prehead <start pitch> <end pitch>
Gives the pitch path for any series of unstressed syllables before the first stressed syllable.
headenv
headenv <envelope> <height>
Gives the pitch envelope which is used for stressed syllables in the head
(before the nucleus), including onset and headlast syllables if these
are specified.
height gives a pitch range for the envelope.
head
head <steps> <start pitch> <end pitch> <unstressed start> <unstressed end>
start pitch give a pitch path for the stressed syllables of the head.
steps is the maximum number of stressed syllables for which this applies. If
there are additional stressed syllables, then the headextend statement is used
for them.
unstressed start give a pitch path for unstressed syllables between two stressed
syllables. Their values are relative to the pitch of the previous stressed syllable.
Values are usually negative, meaning that the unstressed syllables have lower pitch
than the previous stressed syllable.
headextend
headextend <percentage list>
If the head contains more stressed syllables than is specified by steps is used.
It contains up to 8 numbers which are used repeatedly for the additional stressed
syllables. A value of 0 corresponds to the lower the start pitch values of the
head statement. 100 corresponds to the higher value.
Negative values and values greater than 100 are allowed.
nucleus
nucleus <envelope> <top pitch> <bottom pitch> <tail start> <tail end>
This gives the pitch envelope and pitch range of the last stressed syllable of
the clause. tail start and tail end give a pitch path for the unstressed
syllables which are after the last stressed syllable.
nucleus0
nucleus0 <envelope> <top pitch> <bottom pitch>
This is used instead of nucleus if there are no unstressed syllables after
the last stressed syllable. In this case, the pitch changes of the nucleus and
the tail and both included in the nucleus.
onset
onset <pitch> <unstressed start> <unstressed end>
This specifies the pitch for the first stressed syllable of the head. If the
onset statement is present, then the head statement used for the stressed
syllables after the first.
headlast
headlast <pitch> <unstressed start> <unstressed end>
This specifies the pitch for the last stressed syllable of the head (i.e. the stressed syllable before the nucleus).