Studying the phonetic characteristics of glottalized tones in vietnamese expressive speech

MINISTRY OF EDUCATION AND TRAINING HANOI UNIVERSITY OF SCIENCE AND TECHNOLOGY NGUYEN THI LAN Nguyen Thi Lan INFORMATION TECHNOLOGY STUDYING THE PHONETIC CHARACTERISTICS OF GLOTTALIZED TONES IN VIETNAMESE EXPRESSIVE SPEECH MASTER THESIS OF SCIENCE … .INFORMATION TECHNOLOGY 2013B Hanoi – 2015 MINISTRY OF EDUCATION AND TRAINING HANOI UNIVERSITY OF SCIENCE AND TECHNOLOGY Nguyen Thi Lan STUDYING THE PHONETIC CHARACTERISTICS OF GLOTTALIZED TONES IN VIETNAMESE EXPRESSIVE SPEECH Department : INFORMATION TECHNOLOGY MASTER THESIS OF SCIENCE … .INFORMATION TECHNOLOGY SUPERVISOR: Dr Tran Do Dat Hanoi – 2015 COMMITMENT I commit myself to be the person who was responsible for conducting this study All reference figures were extracted with clear derivation The presented results are truthful and have not published in any other person’s work NGUYEN Thi Lan ACKNOWLEDGEMENT This is the second time that I sit here, at Hanoi University of Science and Technology, with a great honor to write these grateful words to people who have been supporting me since the first moment I entered the university The first acknowledgement was written in my graduation thesis 2.5 years ago and today, this one just awakes a special emotion in me I wish to thank all my professors and colleagues at School of Information and Communication Technology and MICA International Research Institute, who have helped me with generous supports Their advice and knowledge they imparted to me are gratefully appreciated, inspiring me a lot to finish this thesis Special thanks to my supervisor Dr Tran Do Dat and colleagues of Speech Communication Department, MICA Institute, including Dr Do Thi Ngoc Diep, Nguyen Thi Thu Trang, Nguyen Tuan Ninh, Tran Thi Anh Xuan, Dr Nguyen Viet Son, Dr Nguyen Cong Phuong, Nguyen Duc Anh and Nguyen Tien Thanh, for their advice and encouragement they gave to me, especially Dr Mac Dang Khoa and Dr Alexis Michaud for their thorough review and invaluable suggestions Another thanks for two thesis reviewers including Assoc Prof Truong Ninh Thuan (VNU) and Dr Vu Thi Huong Giang (SOICT, HUST) for their worth comments which helped the thesis’s presentation become much better Special thanks to my family and friends who always stand by me, lifting me up when I was down Without them, my life would be nonsense! NGUYEN Thi Lan CONTENTS COMMITMENT ACKNOWLEDGEMENT LIST OF ABBREVIATIONS LIST OF TABLES LIST OF FIGURES INTRODUCTION Chapter 1.1 OVERVIEW 11 Background knowledge 11 1.1.1 Vietnamese phonetics and phonology 11 1.1.2 The phonetic characteristics of complex lexical tone system in Vietnamese 15 1.2 Glottalized tones in the context of expressive speech: raising issues 18 1.3 The scope of the thesis 20 1.4 Conclusion 20 Chapter BUILDING VIETNAMESE ATTITUDINAL SPEECH CORPUS FOR SENTENCE-FINAL PARTICLES 22 2.1 Method of using expressive morphemes carrying lexical tones ̶ Sentence-final particles 22 2.2 Designing sample corpus 24 2.3 The progress of building the sample corpus 27 2.4 2.3.1 Elicitation method and speakers 27 2.3.2 Recording conditions 29 2.3.3 Post-processing and annotation 30 Conclusion 32 Chapter ANALYSING VARIATION IN REALIZATION OF GLOTTALIZED TONES BY VARIOUS ATTITUDES 33 3.1 Analysis Method 33 3.2 A pilot data analysis: important new discoveries and an insight into the use of expressive morphemes and glottalized tones 36 3.2.1 Comparison of attitudes: Surprise and Declaration 37 3.2.2 Comparison of attitudes: Irritation and Declaration 38 3.3 Proposals for a full-scale study and statistical analyses of phonation-types based on EGG and DEGG signal 40 3.4 3.3.1 Observation about the irregularities of DECPA 41 3.3.2 Building a tool for detection of creaky and pressed voice in Matlab 44 A full-scale study: detailed analysis results 47 3.4.1 Surprise and Declaration 48 3.4.2 Irritation and Declaration 50 3.5 Discussion 53 3.6 Conclusion 55 CONCLUSION AND PERSPECTIVES 56 REFERENCES 59 PUBLICATIONS 63 APPENDIX A: CONTEXTS OF EACH COLLECTED SENTENCE 63 APPENDIX B: FIGURES OF AVERAGED F0&Oq CONTOURS OF EACH SPEAKER WITH STANDARD DEVIATION FOR THE USED ATTITUDES 67 LIST OF ABBREVIATIONS SFP – Sentence-final particle EGG – Electroglottography DEGG – The derivative of the electroglottography signal IPA – International phonetic association DECPA – Derivative-Electroglottographic Closure Peak Amplitude X-SAMPA – The Extended Speech Assessment Methods Phonetic Alphabet F0 – Fundamental frequency LIST OF TABLES Table 1-1 Vietnamese consonants .12 Table 1-2 Vietnamese vowels/diphthongs 13 Table 1-3 Phonetic characteristics of Vietnamese initial consonants .14 Table 1-4 Phonetic characteristics of Vietnamese final consonants 14 Table 1-5 Phonetic characteristics of Vietnamese vowels/diphthongs .15 Table 1-6 Summarized description of tones of Vietnamese 16 Table 2-1 Intended attitudes 25 Table 2-2 List of speakers 28 Table 3-1 Statistics of Mechanism I-A/Pressed Voice/Mechanism I-B of tone 6a with attitude surprise 50 Table 3-2 Statistics of Mechanism I-A/Creaky Voice/Mechanism I-B of tone with attitude declaration 52 Table 3-3 Statistics of Mechanism I-A/Pressed Voice/Mechanism I-B of tone with attitude irritation 53 LIST OF FIGURES Figure 1-1 Schematic diagram of Hanoi Vietnamese tones (Michaud, 2004a) 18 Figure 2-1 Speaker F7 (left) and M10 (right) in the recording booth .30 Figure 2-2 Sentence and Syllable Level Annotation with SoundForge (above) and Praat (below) of the corpus .31 Figure 3-1 Visualization of closing instant synchronized with EGG (above) and DEGG (below) signals (Henrich, 2001) 34 Figure 3-2 Visualization of opening instant synchronized with EGG (above) and DEGG (below) signals (Henrich, 2001) 35 Figure 3-3 Example of EGG and DEGG signals with indication of glottis closure and opening .36 Figure 3-4 Two realizations of glottalization on SFP /a6a/ with two attitudes (a): declarative/neutral; (b): surprise Speaker M7 37 Figure 3-5 Average curves of F0 and Oq over tokens of /a6a/, speaker M7 38 Figure 3-6 Two realizations of glottalization on SFP /ɗa3/ of two attitudes (a): declarative/neutral; (b): irritation Speaker M6 .39 Figure 3-7 Average curves of F0 and Oq over tokens of /ɗa3/, speaker M6 40 Figure 3-8 Determining mechanisms of voice based on DECPA and F0 parameters (each point of F0&Oq contour corresponds with a cycle on DEGG signal) 42 Figure 3-9 Determining the duration of pressed voice based on local dipping of Oq (each point of F0&Oq contour corresponds with a cycle on DEGG signal) 44 Figure 3-10 The tool for detection integrated three analysis modules 45 Figure 3-11 Some visually illustrative figures of creaky voice from the detection tool .47 Figure 3-12 Some visually illustrative figures of pressed voice from the detection tool .47 Figure 3-13 Averaged F0 contours of SFP /a6a/ of 10 male speakers: surprise and declaration 49 Figure 3-14 Averaged Oq contours of SFP /a6a/ of 10 male speakers: surprise (left) and declaration (right) .49 Figure 3-15 Averaged F0 contours of SFP /ɗa3/ of 10 male speakers: irritation and declaration 51 Figure 3-16 Averaged Oq contours of SFP /ɗa3/ of 10 male speakers: declaration 51 Figure 3-17 Averaged Oq contours of SFP /ɗa3/ of 10 male speakers: irritation 53 Figure 3-18 Proposed model for combination of speaker attitude, voice quality and glottalized tone in Vietnamese expressive speech processing 54 INTRODUCTION Nowadays, using speech in human-machine interaction is gradually becoming the major trend which promises to replace traditional communication methods: mouse, keyboard, screen, for example However, a high-quality human-machine interaction system that can completely behave as a human being, currently, is still just beyond our reach One of the primary reasons is because of the lack of advanced techniques that enable precisely processing (either synthesis or recognition) the expression of human utterances The expression, in other words, refers to attitudinal or emotional aspects when someone speaks, which hereby can convey much linguistic information In this perspective, the attitudinal aspects in speaker utterances, also called speaker attitudes are of no small importance If speaker attitudes play such an important role in the interactions between humans, they need to be taken into account in the interaction between humans and machines (Picard, 1997) Attitudinal information in a spoken utterance can be lexically encoded but can also be conveyed by intonation, including modifications of voice quality (Seibert, 2003) However, the modification of those features in Vietnamese is quite complex since it has the interplay between intonation and tones; especially, the complexity even becomes much more complicated when dealing with glottalized tones which are tone ngã and tone nặng Furthermore, in expressive speech, how the interplay can be expressed, what its realization will be and with which mechanisms, are several among many questions set out Among eight tones in Vietnamese, tone ngã and tone nặng are considered the most complicated since they have glottalization phenomenon accompanied In most cases, with simpler tones, the interaction between intonation and tone simplifies to be described by the changing in fundamental frequency, intensity or duration parameters, whereas with these two glottalized tones, these parameters are exactly local dipping open quotient was taken into account Finally, both obtained qualitative and quantitative results play an important role in demonstrating a new hypothesis on the real mechanism behind production of speaker attitudes, especially in Vietnamese Furthermore, these findings are completely consistent with previous evidenced assertions of the use of specific voice qualities in conveying speaker attitudes Specifically, the difference between attitude declaration and surprise in tone 6a lies in the use of pressed voice and the change in phasing its glottalization from final to medial position while with the pair of attitude declaration and irritation in tone 3, the distinguished factor is shown in using two kinds of voice quality which are creaky voice and pressed voice Besides, the little earlier phasing of glottalization in pressed voice in comparison with that in creaky voice, was also counted Based on the obtained results and to continue with the studied approach, we are going to expand the study to cover wider range of speaker attitudes and more tones in Vietnamese, hoping that these studies would be able to be integrated into speech-based interaction applications as soon as possible Since this is just a preliminary study on this topic, there are lots of future works to in order to provide a complete model for expressive speech processing First, the rest of the corpus needs to be analyzed, including tone and tone in the context of other speaker attitudes such as: Interrogation, Obviousness, Authority and Sarcastic Irony Then, of course, cross-gender study, which is always an attractive topic, will be considered since the speech corpus of female speakers has been completely collected in parallel with that of male speakers In particular, it is supposed that many variations of tones and its glottalization together with the use of other phonation types such as breathy voice or whispery voice are likely to appear Hence, it is necessary to refine the detection and statistical tool so that it can cover many more phenomena Fortunately, the constructed tool was designed following modular approach so it can facilitate integration of more functions Needless to say, all of these short-term objectives above are aimed for a long-term 57 one which is to improve speech interaction-based systems that require higher-level information processing Several ideas for such systems include customer’s satisfaction mining from call centre or automatically emotion-integrated lecture and many other useful applications Our approach definitely promises to be applied for such essential applications 58 REFERENCES Baken, R J 1992 Electroglottography J Voice, 6: 98–110 Brunelle, M 2009a Tone perception in Northern and Southern Vietnamese Journal of Phonetics, 37: 79–96 Brunelle, M 2009b Northern and Southern Vietnamese tone coarticulation: A comparative case study Journal of Southeast Asian Linguist, 1: 49–62 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Emotion Seibert, R 2003 Language and Emotion Oxford University Press The Pangloss Collection n.d http://lacito.vjf.cnrs.fr/archivage/presentation_en.htm Thompson, L 1987 A Vietnamese Reference Grammar University of Hawaii Tran, D.-D., & Castelli, E 2008 Register of Vietnamese tones in continuous speech Presented at the SLTU, Hanoi, Vietnam Tran, H M 1969 Stress, tones and intonation in South Vietnamese Canberra: Australian National University Linguistics Tran, T.-H 2010 Tình thái giảm nhẹ diễn ngơn tiếng Việt [Attenuation in Vietnamese discourse] M.A thesis Ho Chi Minh City Normal University Vu-Ngoc, T., d’ Alessandro, C., & Michaud, A 2005 Using open quotient for the characterization of Vietnamese glottalized tones: 2885–2889 Presented at the Proc of Interspeech, Lisboa 62 PUBLICATIONS International Conference&Workshop Papers: - Nguyen Thi Lan, Alexis Michaud, Tran Do Dat & Mac Dang Khoa, “The interplay of intonation and complex lexical tones: how speaker attitudes affect the realization of glottalization on Vietnamese sentence-final particle” INTERSPEECH 2013, Lyon, France, 2013 National Journal Papers: - Tran Do Dat & Nguyen Thi Lan, “Effect of Sentence-Final Particles on Generation of Fundamental Frequency in Standard Vietnamese” Journal of Science & Technology of Technical Universities in Vietnam, 101 (2014), vol 101, p 171-178, 2014 APPENDIX A: CONTEXTS OF EACH COLLECTED SENTENCE Ba học (Ba goes to school) Intended attitude: declaration Context: when a Ba’s friend asked a Ba’s roommate where Ba went, he only looked forward to a simple answer as Ba had gone to school Ba học Intended attitude: declaration Context: when Ba’s older brother or sister asked a Ba’s roommate where Ba went, he or she only looked forward to a simple answer as well as the sentence Ba had gone to school About the roommate, in order to keep the deep respect for the Ba’s brother/sister, he/she added a SFP “ạ” which is associated lexically with politeness Ba học Intended attitude: declaration Context: when Ba and his/her friend were talking, then the friend asked him whether he had any plan for that whole morning or not and looked forward a simple answer too So Ba said with a normal voice similar to when they were talking before and listed things he intended to including that he needed to go to school 63 Ba học ạ? Intended attitude: interrogation Context: a Ba’s friend came to Ba’s home and met a Ba’s older brother/sister there After hearing from the brother/sister that Ba was not at home at that moment, the friend (thinking of a possibility that Ba may goes to school) asked right away and did not forget to add a SFP “ạ” to show their politeness to the brother/sister, that “Does Ba go to school?” Ba học hả? Intended attitude: interrogation Context: a Ba’s friend came to Ba’s dormitory room and met a Ba’s roommate there After hearing from the roommate that Ba was not there at that moment, the friend (thinking of a possibility that Ba may goes to school) asks right away that “Does Ba go to school?” Ba học ạ? Intended attitude: surprise Context: a Ba’s friend came to Ba’s home and met a Ba’s older brother/sister there After hearing from the brother/sister that Ba was not at home and being at school at that moment, the friend did not think of a possibility that Ba goes to school at all, so this brought him/her a big surprise After that he/she asked right away and did not forget to add a SFP “ạ” to show their politeness to the brother/sister, that “Does Ba go to school?” Ba học mà Intended attitude: surprise Context: a Ba’s friend came to Ba’s dormitory room and met a Ba’s roommate there After hearing from the roommate that Ba was not there and was coming back his hometown at that moment, the friend did not think of a possibility that Ba comes back his hometown at all and that he must be at school, so this brought him/her a big surprise Then he/she said right away that “Ba goes to school! I think so.” Ba học hả? 64 Intended attitude: surprise Context: a Ba’s friend came to Ba’s dormitory room and met a Ba’s roommate there After hearing from the roommate that Ba was not there and being at school at that moment, the friend did not think of a possibility that Ba goes to school at all, so this brought him/her a big surprise Then he/she asked right away that “Does Ba go to school?Really!” Ba học Intended attitude: obviousness Context: a Ba’s older brother/sister came to Ba’s dormitory room and met a Ba’s roommate there After hearing that Ba had went to school, the brother/sister did not believe in the information so he/she asked the roommate to confirm it In order to clearly show the certainty, the roommate asserted again the fact that Ba went to school and of course, he/she should not forget to add a polite SFP 10 Ba học Intended attitude: obviousness Context: on the way to school, Ba received some invitation for hanging out from several friends Still, he/she decided to refuse because of having to go to school at that moment, so he stated firmly the need of going to school right away 11 Ba học mà Intended attitude: obviousness Context: on the way to school, Ba received some invitation for hanging out from several friends Still, he/she decided to refuse because of having to go to school at that moment, so he stated firmly the need of going to school right away 12 Ba học Intended attitude: irritation Context: a Ba’s older brother/sister came to Ba’s dormitory room and met a Ba’s roommate there After hearing that Ba had went to school, the brother/sister did not believe in the information at all, so he/she repeated asking the roommate to confirm it so many times that making the roommate get angry Feeling strange, the 65 roommate started irritated and made the final answer in spite of still adding a polite SFP 13 Ba học Intended attitude: irritation Context: on the way to school, Ba received some invitation for hanging out from several friends Still, he/she decided to refuse because of having to go to school at that moment However, those friends did not let him/her go and continued dragging; Ba finally said irritatingly again that he needed to go to school at once 14 Ba học mà Intended attitude: irritation Context: on the way to school, Ba received some invitation for hanging out from several friends Still, he/she decided to refuse because of having to go to school at that moment However, those friends did not let him/her go and continued dragging; Ba finally said irritatingly again that he needed to go to school at once 15 Ba học Intended attitude: Authority Context: when seeing Ba was too engrossed in playing game, a Ba’s older brother/sister reminded him by a strong command so that Ba must obey him/her to stop playing and go to school at once 16 Ba học Intended attitude: sarcastic irony Context: when Ba was talking with a friend, he suddenly remembered that the time to go to English class had come, so he told the friend that he needed to go Surprisingly, the friend believed that Ba could not be such a hard person in learning English, then he/she repeated Ba’s words by a sarcastic voice 17 Ba học mà Intended attitude: sarcastic irony Context: when Ba was talking with a friend, he suddenly remembered that the time to go to English class had come, so he told the friend that he needed to go 66 Surprisingly, the friend believed that Ba could not be such a hard person in learning English, and then he/she repeated Ba’s words by a sarcastic voice APPENDIX B: FIGURES OF AVERAGED F0&Oq CONTOURS OF EACH SPEAKER WITH STANDARD DEVIATION FOR THE USED ATTITUDES 67 68 69 70 71 ... view of the context set out above, the goal of the present study is to investigate the phonetic characteristics of glottalized tones in Vietnamese expressive speech, focusing on sentence-final... as the phonetic characteristics of lexical tone system in Vietnamese After which, the existing issues and the author’s interests of glottalized tones and expressive speech were given as the main...MINISTRY OF EDUCATION AND TRAINING HANOI UNIVERSITY OF SCIENCE AND TECHNOLOGY Nguyen Thi Lan STUDYING THE PHONETIC CHARACTERISTICS OF GLOTTALIZED TONES IN VIETNAMESE EXPRESSIVE