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IDEAL EMBEDDED SPEECH APPLICATIONS
Accessible appliances
Automotive command and control
Desktop phones
Cellular car kits
Home automation
Cellular handsets
Cordless phones
Instrumentation control
Information kiosks
Internet appliances
ISD-SR3000
Embedded Speech Recognition Processor
EMBEDDED SPEECH RECOGNITION PROCESSOR FOR COMMAND AND
CONTROL APPLICATIONS
The ISD-SR3000 is a complete embedded
speech recognition processor. It consists of a
speech recognition engine, a speech com-
pression engine, and a recording function.
The ISD-SR3000 hardware includes a paral-
lel PISC/DSP core with an optimized instruc-
tion set, a flexible CODEC interface, and a
serial host controller interface.
The speech recognition engine uses sophis-
ticated Hidden Markov Models (HMMs),
which enables recognition of continuous
speech and connected digits. An application
consists of speaker-independent commands
(chosen by the application developer), con-
nected digits and speaker-defined com-
mands. The speaker-defined commands
allow users to sore and recognize voicetags
that can be used for custom commands or
name list management. The speaker-defined
commands use the HMMs, providing much
more robust performance compared to con-
ventional speaker-dependent commands.
The speaker-independent commands, the
audio prompts, and the speaker-defined voic-
etags are stored in external memory, allowing
for maximum application flexibility. Typical
storage requirements are 2kB for each pre-
defined command, 2.5kB for each audio
prompt, and 3kB for each voicetag, including
the model, recording, and data. Application
commands are divided into topics (menus),
with active vocabulary size governed by the
size of the external SRAM. A development
system, the ISD-DS3000, is available. The
development system includes tools for com-
piling and sizing commands and prompts, as
well as sample C-code for host control pro-
gram development.
Advanced Information
IMPORTANT NOTICE:
This product concept and specifications are preliminary and subject to change without notice. Please
contact ISD before using this information in any product design.
September 2000