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A Fully Annotated Corpus of Russian Speech

Pavel Skrelin, Nina Volskaya, Daniil Kocharov, Karina Evgrafova, Olga Glotova, Vera Evdokimova

Department of Phonetics, Saint-Petersburg State University

kocharov@phonetics.pu.ru

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CORPRES

• fully annotated COrpus of Russian Professionally REad Speech

• developed at the Department of Phonetics, Saint-Petersburg State University

• developed for:

– unit-selection TTS

• possible linguistic use:

– research in the Russian phonetics and inter- and intra-speaker speech variability

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Corpus Description

• 8 speakers (4 women and 4 men)

• 60 hours of read speech (7.5 hours from each speaker).

• Texts of different styles:

– fiction narrative texts,

– a play with emotionally expressive dialogues

– informational texts on IT, politics, economy

• 6 levels of annotation.

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Annotation

• Level 1: pitch period boundaries

• Level 2: phonetic events

• Level 3: real phonetic transcription

• Level 4: ideal phonetic transcription

• Level 5: orthographic transcription

• Level 6: prosodic transcription

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Annotated Speech Sample

D. Kocharov, Fully Annotated Corpus of Russian Speech

Annotation file format:0,1,0,2,h0,8,хотелось0,32,h0,64,12286,16,-968,16,

…

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Labeling Periods of Fundamental Frequency andPhonetic Events

• F0 periods were detected automatically.

• The efficiency of automatic F0 detection and F0 period labeling was up to 98%.

• The results of the automatic procedure were checked and corrected manually.

• Phonetic events were detected manually:

– epenthetic vowels,

– voice onsets,

– voiced plosures,

– stationary parts of voiceless consonants,

– glottalization.

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Phonetic Transcription

• Version of SAMPA for Russian was used for transcription.

• 18 symbols were used to mark positional allophones of 6 Russian vowel phonemes /a/, /o/, /i/, /u/, /e/, /y/.

• They contained indication of the vowel’s position regarding stress:

– 0 – stressed accented vowel,

– 1 – unstressed vowel in a pretonic syllable,

– 4 – unstressed one in a post-tonic syllable.

• The set of consonant symbols included 41 symbols:

– 36 Russian consonant phonemes

– 5 voiced allophones of voiceless consonants

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Real Phonetic Transcription

• Speech signal was manually:

– segmented

– transcribed

– peer-revised.

• Huge work!

• Time efficiency: ~1 sound per minute.

=> 1 minute of speech per 1-2 hours.

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Ideal Phonetic Transcription

• Transcription:

– is generated from texts.

• Labels:

– placed automatically to coincide with the label positions produced manually on the real transcription level.

• Automatic labeling:

– not perfect due to the mismatch of ideal and real phonetic transcriptions.

=> results of the automatic procedure were further manually corrected.

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Orthographic and Prosodic Transcription

• Orthographic transcription (Level 5) contains

– the boundaries of words and word labels.

– prosodically prominent words are labeled with special symbols.

• Prosodic transcription (Level 6) contains

– boundaries of tone units and pauses and their labels.

• Prosodic information was marked by expert phoneticians on the basis of perceptual and acoustic analysis of the speech data in a text file containing orthographic transcription.

• Labels were later automatically transferred from the text file to the annotation files to coincide with the phonetic transcription levels.

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Corpus Data Description

D. Kocharov, Fully Annotated Corpus of Russian Speech

Fully Annotated Data

Partly Annotated Data

Total Amount

Phonemes 1 048 867 – –

Words 211 437 317 021 528 458

Tone Units 64 055 86 546 150 601

Hours 24 36 60

40% of the corpus: manually segmented and fully annotated on all six levels.

60% of the corpus: partly annotated

labels for pitch period and phonetic event labels:

no manual phonetic transcription

orthographic, prosodic transcription, ideal phonetic transcription are done, but not aligned with speech signal.

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Mismatch Between Ideal and Real Transcriptions

Total Correctly Mispronounced Elided

Count 1 118 833 947 508 101 292 70 033

Percent 100 84.7 9.05 6.25

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Conclusions

• It is the only available corpus for Russian TTS.

• Precise annotation provides an especially valuable resource for both linguistic research and speech applications development.

• The corpus is large enough for:

– high-quality TTS

– phonetic research of intra- and inter-speaker pronunciation variability

• Our experience shows:

– manual transcription is very expensive, but worth doing.

D. Kocharov, Fully Annotated Corpus of Russian Speech

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Thank you!

D. Kocharov, Fully Annotated Corpus of Russian Speech