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contrary, lip sync error has also been deliberately
used to provoke a humorous affect for the viewer
where the absurd is regarded as comical as opposed
to annoying. For example, the intentionally bad
dubbing for characters in “Chock-Socky” movies
(Tinwell & Grimshaw, 2010).
pants as to how uncanny and how synchronized
speech with lip movement was perceived to be.
(A full description of the stimuli used in the
experiment is provided in the third section.) The
results revealed a strong relationship between
how uncanny a character was perceived to be and
a lack of synchronization between lip movement
and speech: those characters with disparities in
synchronization were perceived as less familiar
and more strange than those characters rated as
close to perfect lip-synchronization.
Synchronization problems with the recorded
voice for early sound cinema heightened a viewer's
awareness that the figure was not real and was
simply a manufactured artifact (Spadoni, 2000, p.
34). A viewer was reminded that figures onscreen
were merely fabricated objects created within a
production studio. The uncanny was increased
as figures were perceived as, “a reassembly of a
figure” easily disassembled within a movie theatre
(Spadoni, 2000, p. 19). The results from the UM
study (Tinwell & Grimshaw, 2010) imply that
the implications of asynchrony for speech and
the uncanny for human figures within the clas-
sic horror cycle of Hollywood film also apply to
virtual characters intended for computer games.
The zombie characters the Witch and the Tank
from the computer game
Left 4 Dead
(2008),
received less than average scores for perceived
lip-synchronization. The jerky, haphazard move-
ment of the Witch's lips appeared disparate from
the high-pitched cries and shrieks spewed out by
this character. As the Witch proceeded to attack,
her presence seemed evermore overwhelming as
sounds appeared to emulate from an incorporeal
and uncontrollable being in a similar manner to
Dracula's laughter noted earlier. Similarly, partici-
pants seemed somewhat confused by the chaotic
movement and irregular sounds generated by the
Tank character making the viewer feel panicked
and uncomfortable.
The stimuli for this study were presented in
different settings and as different actions. Some
were presented as talking heads, for example the
Lip syncing for computer Games
With increasing technological sophistication in
the creation of realism in computer games, text-
based communication systems have been replaced
with virtual characters using actors' voices. To
create full voice-overs for characters, automated
lip-syncing tools extract phoneme sounds from
prerecorded lines of speech. The visual represen-
tation (viseme) for a particular sound is retrieved
from a database of predetermined mouth shapes.
Muscles within the mouth area for a 3D character
are modified to create a particular mouth shape
for each phoneme. Interpolated motion is inserted
between the next phoneme and associated mouth
shape to enable contingency of lip movement for
words within a given sentence. For example, a
specific mouth shape can be selected for the sound
“sh” to be used in conjunction with other sounds
within a word or line of speech. Full voice-overs
for characters were generated for titles developed
by Valve such as
Left 4 Dead
(2008) and
Half
Life 2
(2008) using this technique. A phoneme
extractor tool within
Faceposer
allowed for the
detection and extraction of phoneme sounds from
prerecorded speech to be synchronized with a
character's lips.
Whilst research has been undertaken to im-
prove the motion quality of real-time data driven
approaches for realistic visual speech synthesis
(Cao, Faloustsos, Kohler, & Pighin, 2004), prior
to the UM study (Tinwell & Grimshaw, 2010)
there have been no attempts to investigate what
impact lip-synchronization may have on viewer
perception and the uncanny in virtual characters.
Videos of 13 virtual characters ranging from
humanoid to human were rated by 100 partici-
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