A Review on Acoustic Phonetic Approach for Marathi Speech Recognition
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paper_title: Syllables as concatenated demisyllables and affixes

paper_content:

A method is proposed to decompose English syllables into phonetically and phonotactically well motivated units, so that the complete inventory for segmental concatenation will contain at most 1000 entries and still reproduce natural allphonic variations. A syllable is decomposed into a syllable core and syllable affix(es). Syllable cores have a general form of (Ci) (Ci)V(Cf) (Cf), where V is a single vowel, and Ci and Cf are consonantal elements where Cf may be a glide (semivowel or vowel elongation). The /sp/, /st/, and /sk/ are treated as simple consonantal elements with a place specification, and the ordering of the elements within the core is strictly governed by the vowel affinity principle [Fujimura, IEEE Trans. ASSP‐23, 82–87 (1975)]. The syllable core is divided into initial and final halves—demisyllables each of which can contain only one specification of the place of articulation. The final consonantal elements (such as /s/ in /taeks/) that follow a place‐specified true consonant (/k/ in this case) are treated as syllable affixes. These affixes are all apical, and they observe voicing assimilation with respect to the true consonant in the core.
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paper_title: A preliminary design of a phonetic vocoder based on a diphone model

paper_content:

We report on the initial development of a phonetic vocoder operating at 100 b/s. With each phoneme, the vocoder transmits the duration and a single pitch value. The synthesizer uses a large inventory of diphone templates to synthesize a desired phoneme string. To determine a phoneme string from input speech, the analyzer takes into account the synthesis model by using the same inventory of diphone templates, augmented by additional diphone templates to account for alternate pronunciations. The phoneme string is chosen to minimize the difference between the diphone templates and the input speech according to a distance measure.
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paper_title: The 1976 modular acoustic processor(MAP)

paper_content:

The modular acoustic processor (MAP), a complex experimental system for automatic derivation of phonemic string output for continuous speech, has stages dedicated to signal analysis, spectral classification, phonemic segmentation, phonemic (steady state) classification, phoneme boundary placement, dyadic (transitional) classification, and final phoneme string consolidation. This paper presents the concepts of and some details concerning these five stages. Results on a large body of continuous speech data, prepared by an automatic evaluation system, will also be presented.
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Title: A Review on Acoustic Phonetic Approach for Marathi Speech Recognition

Section 1: INTRODUCTION
Description 1: This section provides an overview of the research problem, the historical context of intermediate units in speech recognition, and the relevance of the study.

Section 2: ACOUSTIC-PHONETIC APPROACH
Description 2: This section explains the principles of the acoustic-phonetic approach, including segmentation and labeling phases, as well as the determination of valid words from segmentation.

Section 3: ACOUSTIC-PHONETIC APPROACH TO MARATHI LANGUAGE SPEECH RECOGNITION (MLSR)
Description 3: This section covers the specific application of the acoustic-phonetic approach to the Marathi language, including a discussion of relevant figures.

Section 4: MARATHI SPEECH SOUNDS AND FEATURES
Description 4: This section describes the unique speech sounds and features of the Marathi language, including classifications of vowels and consonants.

Section 5: Swara (vowels)
Description 5: This section provides detailed information about the 12 vowels (Swara) in Marathi, with examples and their significance for speech recognition.

Section 6: Vyanjana (consonants)
Description 6: This section discusses the consonants (Vyanjana) in Marathi, explaining their importance in the language.

Section 7: C-V STRUCTURE OF SYLLABLE IN MARATHI LANGUAGE
Description 7: This section explains the syllable structure in Marathi, emphasizing the importance of vowels and consonants in forming syllables.

Section 8: EXPERIMENT FOR VOWEL CLASSIFICATION
Description 8: This section details the experiment conducted for vowel classification using LPC and neural networks, including the results shown in figures.

Section 9: CONCLUSION
Description 9: This section summarizes the findings of the study, discusses the recognition rate, applications, and the necessity of extensive knowledge of acoustic properties for the recognition system.

Section 10: FUTURE WORK
Description 10: This section outlines the future directions of the research, emphasizing the scope of developing continuous speech recognition systems for Marathi and other Indian languages.