February
1998, Issue 91
Low-Cost
Voice Recognition
TIME
NORMALIZATION
Words
vary in length. But for this algorithm to work, the
lengths must be normalized to a fixed value.
Each
sample consists of two bytes sampled over one frame
of 256 samples. The unnormalized data in the first 128
bytes of the EEPROM is normalized to a set of 12 vectors
in main RAM.
The
vector in RAM is built up, element by element, by down-
or up-sampling the raw data in EEPROM. Since there are
two elements per feature, a template has a fixed memory
length of 24 bytes.
