Title: Robust Speech Preprocessing for Mobile Applications

Speaker: Prof Nam Soo Kim,
         School of Electrical Engineering, Seoul National University
         currently visiting CMU

Abstract:

These days mobile communication has become an indispensable part
of our daily lives, and has provided a variety of services.
Diversified mobile applications have been available due to the recent
progress in speech processing technologies such as speech coding,
recognition and synthesis. Since, however, there exist many factors
that deteriorate the speech quality, more robust approaches should be
considered when designing a speech application in mobile
communication. In this talk, I present three techniques that have been
developed by our research group to reduce the effects of background
noise and speech coder distortion for mobile communication. The first
one is a soft decision-based spectral enhancement algorithm that
suppresses the noise components and results in a cleaned speech
waveform. The second one is a feature compensation technique referred
to as the interacting multiple model (IMM) approach applied to achieve
robust speech recognition. The last one is a preprocessor that
modifies the signal applied to a low-bit-rate speech coder as an
input. Our research has mainly focused on speech preprocessing
algorithms, which require a minimal modification to the system.