1-2-9೔ຊਓӳ‫ޠ‬Ի੠߹੒ʹ͓͚Δ࿩ऀੑΛอ࣋ͨ͠ӆ཯ิਖ਼๏ͱӳ‫ޠ‬शख़౓͕༩͑ΔӨ‫∗ ڹ‬ˑେౡ༔࢘, ߴಓ৻೭հ, ‫ాށ‬ஐ‫ج‬, Graham Neubig, Sakriani Sakti, தଜ ఩ (ಸྑઌ୺େ)1͸͡ΊʹZ:ƐƉĞĞĐŚ੠࣭ม‫[ ׵‬1] ΍ HMM Ի੠߹੒ [2] Λ༻͍ͨ೔ӳؒΫϩεϦϯΨϧԻ੠߹੒͸ɼಉ‫ؒޠݴ‬ͷ৔߹ͱൺֱͯ͠ɼ࿩ऀੑͷ௿͍ӳ‫ޠ‬Ի੠Λ߹੒͢Δ܏޲ʹ͋Δɽ͜Εʹର͠զʑ͸ɼ೔ຊਓӳ‫ޠ‬ʢERJ: English Readby Japaneseʣ[3] ͷར༻ɼ·ͨɼ೔ຊਓӳ‫ޠ‬ͷӆ཯‫ޡ‬Γʹର͢Δӆ཯ิਖ਼๏ʹΑΓɼ࿩ऀੑΛ‫͘ڧ‬൓өͭͭࣗ͠વੑΛվળ͢Δख๏ΛఏҊ͍ͯ͠Δ [4]ɽ͔͠͠ͳ͕Βɼ೔ຊਓӳ‫ޠ‬ͷࣗવੑ௿ԼͷཁҼͰ͋ΔԻӆ‫ޡ‬Γ͕ߟྀ͞Ε͍ͯͳ͍ͨΊɼಘΒΕΔࣗવੑվળޮՌ͸‫ݶ‬ఆ͞ΕΔɽ·ͨɼ೔ຊਓ࿩ऀͷӳ‫ޠ‬शख़౓ʹର͢Δิਖ਼๏ͷӨ‫ڹ‬΋े෼ʹௐࠪ͞Ε͍ͯͳ͍ɽຊߘͰ͸ɼԻӆิਖ਼๏ͱͯ͠ɼ࿩ऀੑʹର͢ΔӨ‫ڹ‬͕খ͍͞ͱ༧૝͞ΕΔແ੠ࢠԻεϖΫτϧʹର͢Δஔ‫ॲ׵‬ཧΛఏҊ͢Δͱͱ΋ʹɼӳ‫ޠ‬शख़౓ʹର͢Δӆ཯ɾԻӆิਖ਼๏ͷޮՌͷҧ͍Λௐࠪ͢Δɽ࣮‫ݧ‬తධՁ݁ՌʹΑΓɼӆ཯ิਖ਼๏͸ӳ‫ޠ‬शख़౓ʹґଘͤͣɼ࿩ऀੑΛอ࣋ͭͭࣗ͠વੑΛվળͰ͖Δ͜ͱΛࣔ͢ɽ·ͨɼԻӆิਖ਼๏ʹΑΓɼӳ‫ޠ‬शख़౓ͷ௿͍࿩ऀͷࣗવੑΛվળͰ͖Δ͜ͱΛࣔ͢ɽ2ϞσϧదԠʹΑΔӆ཯ิਖ਼๏

Fig. 1 ʹӆ཯ิਖ਼๏ͷखॱΛࣔ͢ɽ໨ඪͱ͢Δ೔ຊ‫ޠ‬฼‫ޠ‬࿩ऀͷ࿩ऀੑΛ൓өͨ͠ӳ‫ޠ‬Ի੠߹੒༻ HMMΛߏங͢ΔͨΊʹɼ໨ඪ࿩ऀͷ೔ຊਓӳ‫ޠ‬Ի੠Λ༻͍ͯɼ ӳ‫ޠ‬฼‫ޠ‬࿩ऀͷ HMM ΛదԠ͢Δɽ೔ຊਓӳ‫ޠ‬Ի੠ͷࣗવੑΛྼԽͤ͞ΔཁҼͱ͠ ͯɼ‫ܧ‬ଓ௕͓Αͼύϫʔʹண໨͠ɼঢ়ଶ‫ܧ‬ଓ௕ͱର਺ύϫʔҎ֎ʹର͢ΔϞσϧύϥϝʔλͷΈΛదԠ͢Δ͜ͱͰɼӳ‫ޠ‬฼‫ޠ‬࿩ऀͷӆ཯Λߟྀͨ͠೔ຊਓӳ‫ޠ‬ͷ HMM Λ
ߏங͢Δɽ

3ແ੠ࢠԻεϖΫτϧஔ‫ʹ׵‬ΑΔԻӆิਖ਼๏

Fig. 2 ʹԻӆิਖ਼๏ͷखॱΛࣔ͢ɽఏҊ๏Ͱ͸ɼӳ‫ޠ‬฼‫ޠ‬࿩ऀͷεϖΫτϧύϥϝʔλΛ෦෼తʹ࢖༻͢Δ͜ͱͰɼ೔ຊਓӳ‫ޠ‬ͷԻӆΛิਖ਼͢Δɽͦͷࡍʹɼ࿩ऀੑΛอ࣋͢ΔͨΊʹɼ࿩ऀґଘੑ͕খ͍͞ͱ༧૝͞ΕΔແ੠ࢠԻʹରͯ͠ͷΈɼิਖ਼ॲཧΛద༻͢Δɽ·ͣɼӳ‫ޠ‬฼‫ޠ‬࿩ऀͷ HMM ͱӆ཯ิਖ਼͞Εͨ೔ຊ‫ޠ‬฼‫ޠ‬࿩ऀͷ HMM ͔ΒɼͦΕͧΕԻ੠ύϥϝʔλΛੜ੒͢Δɽύϥϝʔλੜ੒࣌ʹ͸ɼ‫ܧ‬ଓ௕Ϟσϧͷ໬౓࠷େԽʹΑΓঢ়ଶ‫ܧ‬ଓ௕Λܾఆͨ͠ͷͪɼHMMͷ໬౓࠷େԽʹΑΓύϥϝʔλΛੜ੒͢Δ [5]ɽ͜͜
Ͱɼ֤ HMM ͸ಉҰͷ‫ܧ‬ଓ௕ϞσϧΛ༗͢ΔͨΊɼੜ੒ύϥϝʔλ͸࣌ؒతʹରԠ෇͚ΒΕ͍ͯΔ͜ͱʹ஫ҙ͢Δɽ࣍ʹɼ೔ຊ‫ޠ‬฼‫ޠ‬࿩ऀͷεϖΫτϧύϥϝʔλ‫ྻܥ‬ͷதͰɼແ੠ࢠԻʹରԠ͢ΔϑϨʔϜͷΈΛɼӳ‫ޠ‬฼‫ޠ‬࿩ऀͷεϖΫτϧύϥϝʔλʹஔ‫͢׵‬Δɽͦͷࡍʹɼஔ‫ޙ׵‬ͷεϖΫτϧͱ‫ݩ‬ͷ༗੠ʗແ੠৘ใͷෆҰகʹΑΓੜ͡ΔԻ࣭ྼԽΛճආ͢ΔͨΊʹɼແ੠ࢠԻͷϑϨʔϜʹ͓͚Δӳ‫ޠ‬฼‫ޠ‬࿩ऀͷ F0͕༗੠Ͱ͋Δ৔߹ɼ౰֘ϑϨʔϜΛஔ‫͍ͳ͠׵‬ɽEĂƚŝǀĞŶŐůŝƐŚƐƉĞĞĐŚ^ƉĞĐƚƌƵŵEĂƚŝǀĞ,^DDƐFig. 1EĂƚŝǀĞ,^DDƐFig. 2^ƉĞĐƚƌƵŵǆĐŝƚĂƚŝŽŶWŽǁĞƌWŽǁĞƌƵƌĂƚŝŽŶƵƌĂƚŝŽŶ

Z:,^DDƐǁŝƚŚŵŽĚŝĨŝĞĚƉƌŽƐŽĚǇϞσϧదԠʹΑΔӆ཯ิਖ਼๏^ƉĞĐƚƌĂůƉĂƌĂŵĞƚĞƌ^ǁĂƉƵŶǀŽŝĐĞĚĐŽŶƐŽŶĂŶƚǁŝƚŚEĂƚŝǀĞ͛ƐZ:,^DDƐǁŝƚŚŵŽĚŝĨŝĞĚƉƌŽƐŽĚǇĚĂƉƚǆĐŝƚĂƚŝŽŶ^ǇŶƚŚĞƐŝƐWŚŽŶĞŵĞŵŽĚŝĨŝĞĚƐǇŶƚŚĞƚŝĐƐƉĞĞĐŚŽĨZ:ƐƉĞĂŬĞƌ^ƉĞĐƚƌĂůƉĂƌĂŵĞƚĞƌǆĐŝƚĂƚŝŽŶƉĂƌĂŵĞƚĞƌແ੠ࢠԻεϖΫτϧஔ‫ʹ׵‬ΑΔԻӆิਖ਼๏࣮‫ݧ‬తධՁ44.1 ࣮‫ݧ‬৚ֶ݅शσʔλͱͯ͠ɼCMU ARCTIC Ի੠σʔλϕʔ
ε [6] தͷӳ‫ޠ‬฼‫ޠ‬࿩ऀͷஉঁ֤ 1 ໊ʹΑΔ A ηοτ
593 จΛ༻͍ΔɽదԠσʔλʹ͸ɼ೔ຊਓֶੜʹΑΔ
ಡΈ্͛ӳ‫ޠ‬Ի੠σʔλϕʔε [3] தͷ࠷ߴʢ“High”ʣ΋͘͠͸࠷௿ʢ“Low”ʣӳ‫ޠ‬शख़౓είΞΛ࣋ͭஉঁ‫ ܭ‬4 ໊ʹΑΔ TIMIT[7] 60 จɼ‫ͼٴ‬ɼཹֶ‫ݧܦ‬ͷແ͍உࢠେֶӃੜʢ“Monolingual”ʣͱཹֶ‫ݧܦ‬ͷ͋Δஉࢠେֶੜʢ“Bilingual”ʣʹΑΔ CMU ARCTIC Ի
੠σʔλϕʔε A ηοτ 60 จΛ༻͍ΔɽԻ੠෼ੳ߹੒‫ʹܥ‬͸ STRAIGHT[8] Λ࢖༻͠ɼର਺ύϫʔɼ1 ͔࣍Β 24 ࣍ͷϝϧέϓετϥϜ܎਺ɼର਺ F0 ɼ5 प೾਺ଳҬʹ͓͚Δฏ‫ۉ‬ඇप‫ظ‬੒෼ɼ‫ͦͼٴ‬ΕΒͷ 1 ࣍
ͱ 2 ࣍ͷಈతಛ௃ྔΛԻ੠ύϥϝʔλͱͯ͠༻͍Δɽ
HMM ͸ 5 ঢ়ଶ left-to-right ‫ܕ‬ͷ HSMM[9] ͱ͠ɼର਺ύϫʔͱϝϧέϓετϥϜ܎਺͸ಉҰετϦʔϜͰֶश͢ΔɽϞσϧదԠ͸ CSMAPLR+MAP[10] Λར༻͠ɼճ‫ʹྻߦؼ‬͸੩తಛ௃ྔ‫ͼٴ‬ɼ1 ࣍ͱ 2 ࣍ͷಈతಛ௃ྔʹରԠͨ͠ϒϩοΫର֯ߦྻΛ༻͍Δɽͨͩ͠దԠ࣌ʹ͸ɼదԠσʔλͷ࿩ऀͱಉ͡ੑผͷӳ‫ޠ‬฼‫ޠ‬࿩ऀͷσʔλͰֶश͞Εͨ HMM Λ༻͍Δɽඃ‫ऀݧ‬͸ɼӳ‫ޠ‬฼‫ޠ‬࿩ऀ 6 ໊Ͱ͋ΔɻҎԼͷख๏ʹΑΔ߹੒Ի੠Λ༻͍ͯɼ࿩ऀੑ‫ͼٴ‬ࣗવੑʹؔ͢Δओ‫؍‬ධՁΛ࣮ࢪ͢Δɽ
• HMM+VCɿ ӳ‫ޠ‬฼‫ޠ‬࿩ऀͷ࿩ऀґଘ HSMM ͷग़ྗԻ੠ύϥϝʔλʹରͯ͠ɼGMM ੠࣭ม‫׵‬Λద༻ͯ͠ಘΒΕΔ߹੒Ի੠ [11]• AdaptɿશϞσϧύϥϝʔλΛదԠͤͨ͞దԠ HSMMʹΑΔ߹੒Ի੠
• Dur.+Pow.ɿ ఏҊ๏ͱͯ͠ର਺ύϫʔͱঢ়ଶ‫ܧ‬ଓ௕Ҏ֎ΛదԠͤͨ͞దԠ HSMM ʹΑΔ߹੒Ի੠• Dur.+Pow.+UVCɿ ఏҊ๏ͱͯ͠ Dur.+Pow ʹԻӆิਖ਼Λࢪͨ͠߹੒Ի੠• Nativeɿ ӳ‫ޠ‬฼‫ޠ‬࿩ऀͷ࿩ऀґଘ HSMM ʹΑΔ߹੒Ի੠ධՁ݁Ռ͸ɼӳ‫ޠ‬शख़౓ʢ“High”ͱ “Low”ʣຖʹ‫ܭ‬ࢉ͢Δɽͨͩ͠ɼ“Monolingual”ͱ “Bilingual”͸ͦ∗Prosody Correction Preserving Speaker Individuality in English-Read-By-Japanese Speech Synthesis andEffects of English Proficiency Level, by OSHIMA, Yuji, TAKAMICHI, Shinnosuke, TODA, Tomoki,NEUBIG, Graham, SAKTI, Sakriani, NAKAMURA, Satoshi (NAIST)

日本音響学会講演論文集- 243 -2015年3月

ϱ

4.2.2 Իӆิਖ਼๏ͷޮՌਤ 5ɼ ਤ 6 ʹͦΕͧΕɼԻӆิਖ਼๏ʹର͢Δ࿩ऀੑͱࣗવੑʹؔ͢Δओ‫؍‬ධՁ݁ՌΛࣔ͢ɽ“Low”
ʹରͯ͠ɼ“Dur.+Pow.+UVC”͸ “Dur.+Pow.”ͱൺ
ֱͯ͠ɼ࿩ऀੑΛಉ౳ఔ౓ʹอ࣋ͭͭࣗ͠વੑΛվ
ળͰ͖Δ͜ͱ͕෼͔Δɽ·ͨɼ“High”ʹରͯ͠͸ɼ“Dur.+Pow.+UVC”͸ “Dur.+Pow.”ͱಉ౳ͷࣗવੑ͓Αͼ࿩ऀੑΛอ࣋Ͱ͖Δ͜ͱ͕෼͔Δɽ

5͓ΘΓʹຊߘͰ͸ɼϞσϧదԠʹΑΔ೔ຊਓӳ‫߹ޠ‬੒Ի੠ͷӆ཯ิਖ਼๏Λӳ‫ޠ‬शख़౓ͷҟͳΔෳ਺࿩ऀʹద༻͠ɼ࿩ऀੑͱࣗવੑʹؔ͢Δओ‫؍‬ධՁΛ࣮ࢪͨ͠ɽओ‫؍‬ධՁ݁ՌΑΓɼຊఏҊ๏͸ӳ‫ޠ‬शख़౓ʹґଘͤͣɼ࿩ऀੑΛอ࣋ͭͭࣗ͠વੑΛվળͰ͖Δ͜ͱΛࣔͨ͠ɽ·ͨɼ෦෼తͳԻӆิਖ਼๏ͷఏҊ΋ߦ͍ɼӳ‫ޠ‬शख़౓ͷ௿͍࿩ऀʹରͯ͠ɼࣗવੑΛվળͰ͖Δ͜ͱΛࣔͨ͠ɽࠓ‫ޙ‬͸ɼ໌ྎ౓ʹؔ͢ΔධՁ͓Αͼ໨ඪ࿩ऀຖͷԻӆ‫ޡ‬Γʹ‫࠷ͮ͘ج‬దͳิਖ਼๏Λ‫ݕ‬౼͢Δඞཁ͕
͋Δɽ

日本音響学会講演論文集ϵϱйŽŶĨŝĚĞŶĐĞŝŶƚĞƌǀĂůϰDK^

DK^ϰϯϯϮϮϭ

ϭ,ŝŐŚ,ŝŐŚ>Žǁ

>Žǁ

Fig. 3 ӆ཯ิਖ਼๏ʹର͢ Fig. 4 ӆ཯ิਖ਼๏ʹର͢Δ࿩ऀੑʹؔ͢Δओ‫؍‬ධՁ Δࣗવੑʹؔ͢Δओ‫؍‬ධՁ݁Ռ݁ՌϭϭϵϱйŽŶĨŝĚĞŶĐĞŝŶƚĞƌǀĂůϵϱйŽŶĨŝĚĞŶĐĞŝŶƚĞƌǀĂůϬ͘ϴϬ͘ϴWƌĞĨĞƌĞŶĐĞƐĐŽƌĞ

4.2 ࣮‫݁ݧ‬Ռ
4.2.1 ӆ཯ิਖ਼๏ͷޮՌ
ਤ 3ɼ ਤ 4 ʹͦΕͧΕɼӆ཯ิਖ਼๏ʹର͢Δ࿩
ऀੑͱࣗવੑʹؔ͢Δओ‫؍‬ධՁ݁ՌΛࣔ͢ɽGMM
੠࣭ม‫׵‬Λར༻ͨ͠ख๏ “HMM+VC”ʹண໨͢Δͱɼ
“Low”ʹ͓͍ͯɼશϞσϧύϥϝʔλΛదԠͨ͠ख๏
“Adapt”ͱൺֱͯ͠ɼ࿩ऀੑ͕େ͖͘ྼԽ͢Δ܏޲͕‫ݟ‬ΒΕΔɽ“High”ʹ͓͍ͯ΋ɼྼԽͷఔ౓͸খ͘͞ͳΔ͕ɼಉ༷ͷ܏޲͕‫ݟ‬ΒΕΔɽఏҊ๏ͷ‫ܧ‬ଓ௕͓ΑͼύϫʔΛิਖ਼ͨ͠ “Dur.+Pow.”ʹؔͯ͠͸ɼӳ‫ޠ‬शख़౓ʹؔ܎ͳ͘ “Adapt”ͱಉ౳ͷ࿩ऀੑΛอ͍ͬͯΔ͜
ͱ͕෼͔ΔɽҰํɼࣗવੑʹؔͯ͠͸ɼ“Dur.+Pow.”
͸ “HMM+VC”ͱಉ౳ͱͳΔɽ“Adapt”ͱൺֱ͢Δͱɼࣗવੑ͕վળ͞Ε͓ͯΓɼ“Low”ʹର͢ΔվળޮՌ͕ஶ͍͠ɽҎ্ͷ݁Ռ͔Βɼӳ‫ޠ‬शख़౓ͷߴ௿ʹؔΘΒͣɼఏҊ๏͸‫ʹ݈ؤ‬ಈ࡞͢Δ͜ͱΛ֬ೝͰ͖ɼ‫ܧ‬ଓ௕‫ͼٴ‬ύϫʔิਖ਼ʹΑΓɼ೔ຊਓӳ‫ޠ‬ͷ࿩ऀੑΛอ࣋ͭͭ͠ɼࣗવੑͷߴ͍ӳ‫ޠ‬Ի੠Λ߹੒Ͱ͖Δ͜ͱ͕෼͔ΔɽϱϵϱйŽŶĨŝĚĞŶĐĞŝŶƚĞƌǀĂůWƌĞĨĞƌĞŶĐĞƐĐŽƌĞΕͧΕɼ“Low”ͱ “High”ʹଐ͢Δ΋ͷͱ͢Δɽӆ཯ิਖ਼๏Λ༻͍ͨ࿩ऀੑͷධՁͰ͸ɼ೔ຊ‫ޠ‬฼‫ޠ‬࿩ऀͷ೔ຊਓӳ‫ޠ‬෼ੳ߹੒Ի੠ΛϦϑΝϨϯεͱͨ͠
5 ஈ֊ DMOSʢDegradation Mean Opinion ScoreʣධՁΛ࣮ࢪ͢ΔɽධՁ͢Δख๏͸ɼ“HMM+VC”ɼ
“Adapt”ɼ“Dur.+Pow.”ͷ 3 ͭͰ͋ΔɽࣗવੑͷධՁͰ͸ɼӳ‫ޠ‬Ի੠ͷࣗવੑʹؔ͢Δ 5 ஈ֊ MOSʢMeanOpinion ScoreʣධՁΛ࣮ࢪ͢ΔɽධՁ͢Δख๏͸ɼ“HMM+VC”ɼ“Adapt”ɼ“Dur.+Pow.”ɼ“Native”ͷ
4 ͭͰ͋Δɽͨͩ͠ɼ “Monolingual”ͱ “Bilingua”ͷ
దԠσʔλʹ͍ͭͯ͸ɼ[4] ͰධՁ͍ͯ͠ΔͨΊɼຊߘͰ͸࢖༻͠ͳ͍ɽԻӆิਖ਼๏Λ༻͍ͨ࿩ऀੑͷධՁͰ͸ɼ೔ຊ‫ޠ‬฼‫ޠ‬࿩ऀͷ೔ຊਓӳ‫ޠ‬෼ੳ߹੒Ի੠ΛϦϑΝϨϯεͱͨ͠ϓϦϑΝϨϯεςετ (XAB ςετ) Λ࣮ࢪ͢ΔɽධՁ͢Δख๏͸ɺ“Dur.+Pow.”ɺ“Dur.+Pow.+UVC”ͷ
2 ͭͰ͋ΔɻࣗવੑͷධՁͰ͸ɼӳ‫ޠ‬Ի੠ͷࣗવੑʹؔ͢ΔϓϦϑΝϨϯεςετ (AB ςετ) Λ࣮ࢪ͢Δɽධ Ձ ख ๏ ͸ ɼ“Dur.+Pow.”ɼ“Dur.+Pow.+UVC”ɼ
“Native”ͷ 3 ͭͰ͋ΔɻϬ͘ϲϬ͘ϰϬ͘ϲϬ͘ϰϬ͘ϮϬ͘ϮϬϬ,ŝŐŚ>Žǁ

,ŝŐŚ>Žǁ

Fig. 5 Իӆิਖ਼๏ʹର͢ Fig. 6 Իӆิਖ਼๏ʹର͢Δ࿩ऀੑʹؔ͢Δओ‫؍‬ධՁ Δࣗવੑʹؔ͢Δओ‫؍‬ධՁ݁Ռ݁Ռँࣙ ຊ‫ڀݚ‬ͷҰ෦͸ɼʢಠʣ৘ใ௨৴‫ߏػڀݚ‬ͷҕୗ‫ڀݚ‬ʮ஌ࣝɾ‫ޠݴ‬άϦουʹ‫ͮ͘ج‬ΞδΞҩྍަྲྀࢧԉγεςϜͷ‫ڀݚ‬։ൃʯ͓Αͼ JSPS Պ‫ݚ‬අ 26280060ͷॿ੒Λड͚࣮ࢪͨ͠΋ͷͰ͋Δɽࢀߟจ‫ݙ‬[1] T. Toda et al., IEEE Trans. ASLP, Vol. 15, No.
8, pp. 2222–2235, 2007.
[2] K. Tokuda et al., Proc. IEEE, Vol. 101, No. 5,pp. 1234–1252, 2013.
[3] N. Minematsu et al., Proc. ICA, Vol. 1, pp.
557–560, 2004.
[4] େౡ ଞ, ৴ֶٕใ, Vol. 114, No. 365, SP2014111, pp. 63–68, 2014.
[5] K. Tokuda et al., Proc. ICASSP, Vol. 3, pp.
1315–1318, 2000.
[6] J. Kominek et al., Tech Report., CMU-LTI-03177, 2003.
[7] J. Garofolo et al., Tech Report., NISTIR 4930,NIST, 1993.
[8] J. Yamagishi IEEE Trans. ASLP, Vol. 17, No.
6, pp. 1208–1230, 2009.
[9] H. Kawahara et al., Speech Commun., Vol. 27,No. 3–4, pp. 187–207, 1999.
[10] H. Zen IEICE Trans. Inf. and Syst., Vol. 90,
No. 5, pp. 825–834, 2007.
[11] N. Hattori et al., Proc. INTERSPEECH, pp.
2769–2772, 2011.

- 244 -2015年3月