3-6-10   "!$# %'& (*)+# ,- .0/13254768479 :;=<7>@?BA=CBDFEHG3I=J7KBLBMONBP∗( ) NTT

WxzyYX[{}QSZ]|8RU\B~8T*^`UV_ acetbcf_Yd`@eF fh~ g5_UikdUj`e_mflo8nYprzqtrs=uwv |Y§¨5l7Ug5q=ic©U_Yªr\td r]~=F{`«t`F¬U8~­[[®Y`jU¯rY_]g nUiY=ptjUB_U¡r°tqF7±0¢hh£¤l²7nUOt_]p'\dt³`i7¥`´`¦µFÀ`¶¤Áz· ÂmqOÃÅ¸[Ä¹tÆ[Çtrql7szºÈÉjF»8_¼ ~ k°\¤UU± aB{=bB½]e]¾Uf¿ qBi ÊawvYg=iinY¥`pt¦}³BÐ´r+HË»OUbFÌ}ÑtakqUvFgºUiY jU{ _]ak°¤'±0a@l²i]n]shprÈÅ³`Í`´Î¤BÒÏUUºO¦0_`d av8ÓFÙUÔÕÚr\OrgiY5ÖjU_×5\]l@¤nUØ'p}»`Û{ [Ühq=°¤±zO_Ud¥`¦§âtãkÝ`\=Þ¤ÝYÞt {â jYv _| lß n`tpu5tlb ~8¼Bg=qci5°[ä[±Uå¤tqYwg=à8ic§tjY_`á ° |±¤³8´táBªUg5æ[i5Ü`icçí5ê`è`ëzé`ê`q8ët¢¤\5£`WY[ìîï Äzâ ðH ñ`~ ò qO`Ê akvlYi7aHn`v5pó
ë'â ÈÅôqcqYù]¢]ãBâú[£UvºYcv8n`×=ibpY|³Y ´lceFq]§}f s8wÝ~c [û[{YÞ"ü¤õwaBöýYb þ 7Ä gw{ ÷YkçÙFYø¤Útèicé`\]çYêYèYg8ëté`i ê\ |ÿ t§} qr{ s'ÝYÈ ÞYzÑ§z¤g5bi ti|B~ý`þ  Ä â ~ b    ® ® ð ðH÷BÌº[v F_FdFÎ e¤éf'=w÷ht {|lwº}»`aw» ävY"iYÝFaBÞ`b=§rà§r\]\Yg8ii
 ä ~ [jY _`Â °[­ ±mloYn`!p]³´¤acá #v û" $r râ  áF{ i ÙY%UÚté \U g5 i Â ä&­  ~ ' q)¼ (*,q +.-]\z×Y {1Dt ,ωSt ,ω_[d~À`Áz ® Âm@ÀÃÅFÁrÄç`ÂÕ è[ÎhÃ é"Ä#\AlY =Õa7Î  vâ i Ü[{ í g=qi ¢]i £[~St,l Yt,lSt,l1

Yt,l1
Dt,lXt,lYt,lXt,l =KlXg∗k,l Xt−k,l + St,l(2)k}×)l ¾Am g%nU©o¨L=] { \]g=i&phqrsd'g=ç¤èUéuthl5qHvAwYxdlFaOv#=h'lcºÕ»qY| }¢tl=¡£UBi~8~y xd !yawv¤~ ºtOð z {¬c{ {A|Fét\]¤ g8{ i`ç[èFé2s σt|At (ejω )|2At (z) =1 − at,1 z−1 − · · · − at,P z−P(2) St,l(3)0g1,l , · · · , gKl ,l∗s λt (2πl/N)

b Bha igOi) ik©  Ð ¶ ~%n '~  Îé\]¤ {j¤_g æhl`\ha7]v Y { Ü[_ í ~uq!®À[a Á' Â0º |Ã3Älw q!Î Zi
g  i ~ %n   q'aBbYáÕ» {p(St,l ) = NC {St,l ; 0, s λt (2πl/N)}(5)

NC {x; µ, Σ}Σt0Dt,ld λ(2πl/N)ü  · ~q# (t,zl,\t ,tl  ) q{ å]ã º[bv`i i S l D g û ¿ i S l S i!DOE D (t,l Dl) 6= (tg,, l )) #p(Dt,l ) =NC {Dt,l ; 0, d λ(2πl/N)}
00t,l(6)t 0 ,l 00 0\]U {l}  ~ y ¨²i8ÛÜ~
#t~L#  ÎBétgci
ij ~ sh»cq ¡£U {t,lt 0 ,l 0t,lt 0 ,l 0

Y = {Yt,l }0≤t≤T −1,0≤l≤N−1{Xt,l }0≤t≤T −1,0≤l≤N−1p(Y, X; Θ) ∝N−1Yd λ(2πl/N)−T

l=0T−1 N−1XX
t=0 l=0lµd λ(ω)

(4)

(4)

2s σtat,k× exp −(2)(3)

l g _ âO`8â i  QzqY¢t£[  |Fé DE  n ~? ®l I\]¤ {~ %n q'aO!g bYáÕ » { i k=1∗

Ps λt (ω) =(1)Yt,l =Xt,l + Dt,lts λt (ω)

t (0 ≤ t ≤ T −1)l (0 ≤ l ≤ N − 1)

STFTYt ,ω(1) ω ∈ [−π, π)[2]Ù { ÙÚt/1Úz\U03gB25ª?iO47>@Yv5Ö[69i v 8;Ü~ í:;eF < fr OÜþ YÂcí=À çYè`éYê`ë]\=`ìU
Y\b iABr@Fa ç`i=Yè`Ö[é v  ~  eUþ ftÂ=g5À i5Ü`íC[D.E FHG \A]=t\ I {ç[íJhèF[ éqLSOK[Pî ÙQ0\Y¨&® l[]acâ v]îFvFïg8ºUÄi ¤Rh!ð ¼ ^ÜU~ ír lHÂîY]IT®  OÌSV{ hUA ºtWX MO{ NY i5Ü`í Zâ {[ _`{ d`b g=e¤&i f~ b lnF`pULq _¤cte¤dF# fetdrOifqtl s_ jUuBâ_Uv8`=e]i â f¨5ih}i _ f âe#g`la=â bYáriLu=DOv E eg} â lYza8stlk» {] |B~ l=×ki g,ijrqra+b 1 F e]f ~ eg [1]2X t ,ω  +|At (ej 2πlN2s σt)|2−1
TY

X=( s σ2t )−N

t=0|Yt,l − Xt,l |2d λ(2πl/N)|Xt,l −KlXg∗k,l Xt−k,l |2(7)k=1Simultaneous Suppression of Noise and Reverberation for Speech Enhancement, by Takuya Yoshioka,
Tomohiro Nakatani, and Masato Miyoshi. (NTT Communication Science Laboratories)

日本音響学会講演論文集- 731 -

2008年3月

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ð ~ ¢ \]U {Θ = { s Θ, g Θ, d Θ}=sΘ
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gΘ = gΘ^s Θ ← s Θ̃tPKl ∗^k,l Xt−k,l |2 ir(X)k=1 g∗ H0,l∗T −1,llx Rt =lllr(X)g Θ̃
gl = [g∗1,l , · · · , g∗Kl ,l ]Hg̃l = x R−1
x rttllh|Xt,l −Ç lkhaoi zl@i gl ~Ui ~# ~  { sh¡`\c»c÷qtÑ[] â  { ü(4) (CM-step2)^q(Ψ) s Θ = s Θ^g Θ ← g Θ̃g̃lp(x)

ls Θ̃

s Θ̃

T−1X(11)j 2πlN^ t (eA)
hxt−1,l xHt−1,l ir(X) (12)
2σ
^
stt=0

T−1 ^X

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Hl lllllHlll

H −1lHll∗HKl ,l∗1,ll(4)^ t (z)xt,l = [X∗t,l , · · · , X∗t−Kl +1,l ]H A
at,k = a^ t,k(5)

(2)

l−1/2

s T −tl−1/2

d T −tT −t,ll

JNASt,l^t,l = µt,l −SKlX

103g∗k,l µt−k,l(10)8 kHz

0.5k=1SNΘ

10 dBdΘSN^dΘΨ = { s Θ, g Θ}

YSTFT128
Kl = 30 (0 ≤ l ≤ N − 1),Ψ^ΨSNΨ

1TEMXX^ d Θ)^^r(X) = p(X|Y; Ψ,ΨEM^ r(X)q(Ψ) = hlog p(Y, X; Ψ, d Θ)i
^
Ψ

T−1X
t=0SASNRPN−1|St,l |210 log10 PN−1 l=0||St,l | − |S^t,l ||2(dB) (14)l=0SASNR

7.72 dBΨ̃q(Ψ)sΘECM

P = 12 ECM

5^p(Y; Ψ, d Θ)

(7)

256gΘ

SASNR
4.46 dB 1.49 dB

EM

Ψ(1)

^ = { s Θ,
^ g Θ}^Ψ(2) (E-step)Q^ ^r(X) = N−1
l=0 p(Xl |Y; Ψ, d Θ)

日本音響学会講演論文集

Xl[1] K. Kinoshita, et al., Proc. Interspeech’07, pp. 854–857, 2007.
[2] T. Nakatani, et al., Proc. ICASSP’08, accepted,2008.

- 732 -2008年3月