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196 Chapter 11

of speech that is reminiscent of a tonal dialect. As it stands, the output is quite distinctive
and contributes significantly to Kismet’s personality (as it pertains to its manner of vocal
expression).Itisreallyintended,however,asaplaceholderforamoresophisticatedutterance
generation algorithm to eventually replace it. In time, Kismet will be able to adjust its
utterance based on what it hears, but this is the subject of future work.
Based upon DECtalk’s phonemic speech mode, the generated string to be synthesized
is assembled from pitch accents, phonemes, and end syntax. The end syntax is a require-
ment of DECtalk and does not serve a grammatical function. However, as with the pitch
accents, it does influence the prosody of the utterance and is used in this manner. The
DECtalk phonemes are summarized in table 11.6 and the accents are summarized in
table 11.7.

Table 11.6
DECtalk phonemes for generating utterances.
Consonants Vowels Vowels

b bet n net aa bob oy boy
ch chin nx sing ae bat rr bird
d debt p pet ah but uh book
dh this r red ao bought uw lute
el bottle s sit aw bout yu cute
en button sh shin ax about allophones
f fin t test ay bite dx rider
g guess th thin eh bet lx will
hx head v vest ey bake q weeat
jh gin w wet ih bit rx oration
k ken yx yet ix kisses tx Latin
l let z zoo iy beat Silence
m met zh azure ow boat (underscore)

Table 11.7
DECtalk accents and end syntax for generating utterances.
Symbol Name Indicates Symbol Name Indicates
[’] apostrophe primary stress [,] comma clause boundaries
[‘] grave accent secondary stress [.] period period
[“] quotation mark emphatic stress [?] question mark question mark
[/] slash pitch rise [!] exclamation mark exclamation mark
[\] backslash pitch fall [ ] space word boundary
[/ \] hat pitch rise and fall