Speech Recognition Application

1
Speech Recognition Application

• Voice Enabled Phone Directory
• - Yousef Rabah

2
Process of Speech Recognition

• Speaker dependent vs. Speaker Independent
• Vocabulary ? Isolated vs. Continuous
• Frequency changes
• Pronunciation
• Speech Processing
• HMM Probabilities, Parameters, Training
• Phonemes to words

3
Problem

• Automatic speech interacting phone directory
  assistance without human interaction.

4
Automatic Speech Recognition - Sphinx

• Acoustic modeling
• Language Model
• Unigrams
• Bigrams P(word2 word1)
• Trigrams P(word3 word2 word1)
• Lexicon Structure
• ZERO Z IH R OW
• ONE W AH N
• TWO T UW

5
Input / Output

• 24003 samples in file /usr/local/share/sphinx3/mod
  el/lm/an4/hell.raw
• INFO live.c(239) live_nfeatvec 13
• INFO main_live_pretend.c(92) PARTIAL HYP
• INFO live.c(239) live_nfeatvec 12
• INFO main_live_pretend.c(92) PARTIAL HYP
  A(2)
• INFO live.c(239) live_nfeatvec 13
• INFO main_live_pretend.c(92) PARTIAL HYP
  EIGHTH
• INFO live.c(239) live_nfeatvec 12
• INFO main_live_pretend.c(92) PARTIAL HYP
  H
• INFO live.c(239) live_nfeatvec 13
• INFO main_live_pretend.c(92) PARTIAL HYP
  H E
• INFO live.c(239) live_nfeatvec 12
• INFO main_live_pretend.c(92) PARTIAL HYP
  H E
• INFO live.c(239) live_nfeatvec 13
• INFO main_live_pretend.c(92) PARTIAL HYP
  H E L
• INFO live.c(239) live_nfeatvec 12
• INFO main_live_pretend.c(92) PARTIAL HYP
  H E L
• INFO live.c(239) live_nfeatvec 13
• INFO main_live_pretend.c(92) PARTIAL HYP
  H E L OH

• Backtrace(null)
• LatID SFrm EFrm AScr LScr Type
• 254 0 45 -391470 -74100 -1
• 594 46 81 -472155 -148846 0 H
• 1291 82 102 -288621 -148846 0 E
• 1850 103 126 -235274 -148846 0 L
• 2599 127 147 -430694 -148846 0 L
• 2650 148 148 0 -148846 0
• 0 148 -1818214 -818330 (Total)
• FWDVIT H E L L (null)

6
Difficulties

• Hardware issues
• ASR software issues
• Letter phonemes - e-set
• Time

7
Solution

• Database (PostgreSQL)
• Names
• Numbers
• Phone number
• Fast access

8
Solution

• Example (general idea)
• PC Say the letters of first name, press space
  bar before and after you speak
• User S AA EM
• PC Did you say, SAM ?

• Architecture of application
• User Interaction
• Connects to Database
• Communicates with Sphinx
• Uses of C, Perl, shell scripts

9
Solution
10
Check List

• Reading
• ASR system
• Database - PSQL
• Applications in C, Perl, PHP, vxml, shell

11
Timeline