Text-To-Speech System for MarathiText-To-Speech System for Marathi

Miss. Deepa V. KadamMiss. Deepa V. Kadam

Indian Institute of Technology, Indian Institute of Technology, BombayBombay

Text-to-SpeechText-to-Speech SynthesisSynthesis

Text-to-Speech (TTS) synthesizer :Text-to-Speech (TTS) synthesizer : It is a computer based system that should be able to It is a computer based system that should be able to

read any text aloud whether it was directly read any text aloud whether it was directly introduced in the computer by an operator or introduced in the computer by an operator or scanned and submitted to an Optical Character scanned and submitted to an Optical Character Recognition (OCR) systemRecognition (OCR) system

Voice response system are application of speech Voice response system are application of speech synthesis technology and broadly classified in two synthesis technology and broadly classified in two types types

1. Limited vocabulary system1. Limited vocabulary system 2. Unlimited vocabulary system2. Unlimited vocabulary system

General functional diagram of General functional diagram of Text-to-Speech systemText-to-Speech system

Text

NATURAL LANGUAGE PROCESSING

Linguistic FormalismInference EnginesLogical Inferences

DIGITAL SIGNAL PROCESSING

Mathematical ModelsAlgorithms

Computations

Phonemes

Prosody

Speech

TEXT-TO-SPEECH SYNTHESIZER

Human Speech Production SystemHuman Speech Production System

Text Analysis Document Structure Detection Text Normalization Linguistic Analysis

Prosodic Analysis Pitch & Duration attachment

Speech Synthesis Voice Rendering

Raw text or tagged text

Tagged text

Tagged phone

Controls

Phonetic Analysis Grapheme-to-Phoneme Conversion

Architecture of TTS systemArchitecture of TTS system

Concatenative SynthesisConcatenative Synthesis

• It requires neither rules nor manual It requires neither rules nor manual tuning.tuning.

• Stores segmentsStores segments• Choice of segmentsChoice of segments• eg. Words, Syllables, Demi-eg. Words, Syllables, Demi-

syllables, Diaphones, syllables, Diaphones, Phones.Phones.• Segment concatenationSegment concatenation

Text-to-SpeechText-to-Speech Synthesis System for Synthesis System for Marathi LanguageMarathi Language

1. Marathi Script1. Marathi Script2. Design of Synthesizer2. Design of Synthesizer a. Speech Synthesis Modela. Speech Synthesis Model b. Structure of Databaseb. Structure of Database c. Linguistic Rulesc. Linguistic Rules3. Implementation of Synthesizer3. Implementation of Synthesizer a. Database Creationa. Database Creation b. Algorithmb. Algorithm c. Applying Rules c. Applying Rules

AlgorithmAlgorithm

• Initialize the programInitialize the program- Initialize GUI.- Initialize GUI.- Load all sound files in Buffer array.- Load all sound files in Buffer array.- Load default values of rules.- Load default values of rules.

• On key type event (Marathi keyboard help)On key type event (Marathi keyboard help)- If typed key does not form a text which is - If typed key does not form a text which is

displayed in displayed in loaded help, then remove the loaded help, then remove the old help table and load a old help table and load a new help which new help which displays a possible combinations of displays a possible combinations of typed typed consonant followed by all vowels.consonant followed by all vowels.

• Display Marathi textDisplay Marathi text

- Read Marathi readable text (English - Read Marathi readable text (English format).format).

- Convert it to text which is - Convert it to text which is equivalent to script equivalent to script use by Marathi font use by Marathi font (KIRAN) to display it in (KIRAN) to display it in Marathi. Marathi.

- Output this converted text to the - Output this converted text to the other text box other text box whose font is set to whose font is set to Marathi script.Marathi script.

• Synthesize speechSynthesize speech

- Read Marathi readable text (English format)- Read Marathi readable text (English format)- Normalize input text.- Normalize input text.- Parse this text into words.- Parse this text into words.- Parse these words into phonemes (Speech Units).- Parse these words into phonemes (Speech Units).- For each word, process all units as follows- For each word, process all units as follows

* Get index of Unit* Get index of Unit* Get index of previous and next unit* Get index of previous and next unit* Calculate the values of Length, decay * Calculate the values of Length, decay

and and silence by applying rules. silence by applying rules.* Apply these values to the indexed * Apply these values to the indexed

speech speech segment. segment.

• On amplify event the synthesize On amplify event the synthesize speechspeech

• On waveform Event draw waveform On waveform Event draw waveform of synthesizeof synthesize

Speech Synthesis FeaturesSpeech Synthesis Features• This interface has two text areas. One for inputting This interface has two text areas. One for inputting

Marathi text in English and other for displaying Marathi text in English and other for displaying equivalent text in Marathi. equivalent text in Marathi.

• This interface also provides help for typing Marathi This interface also provides help for typing Marathi with the help of normal keyboard. It displays how to with the help of normal keyboard. It displays how to type all related Marathi phonemes which begin with type all related Marathi phonemes which begin with last character typed.last character typed.

• The waveform button shows the waveforms for The waveform button shows the waveforms for output speech signal.output speech signal.

ApplicationsApplications

1. Talking Calculator1. Talking Calculator

2. Computer generated wiring instruction2. Computer generated wiring instruction

3. Aids for the blind3. Aids for the blind

4. Telephone inquiry service4. Telephone inquiry service

5. Teaching machines5. Teaching machines