MUC LUC GVHD: PHAN NGUYEN PHUC QUOC

LUAN VAN TOT NGHIEP - iii - SVTH: HA THUC PHUNG

MUC LUC

Li cam n ......................................................................................................................... i

Tom tat ........................................................................................................................ ii

Muc luc ....................................................................................................................... iii

Chng 0: M AU ................................................................................................................. 1

Chng 1: GII THIEU VE TIENG NOI VA NHAN DANG TIENG NOI ..................... 3

I. Nhng van e c ban cua tieng noi .............................................................................. 3

1. Bo may phat am cua con ngi ........................................................................ 3

2. C quan thnh giac cua con ngi .................................................................... 7

3. Ng am tieng Viet ............................................................................................. 9

II. Tong quan ve nhan dang tieng noi ............................................................................. 10

1. S lc ve nhan dang tieng noi ....................................................................... 10

2. Phan loai .......................................................................................................... 10

3. Cac hng nghien cu nhan dang tieng noi ................................................... 11

III. Tom tat ...................................................................................................................... 13

Chng 2: C S X L SO TN HIEU.............................................................................. 15

I. Chuoi so ...................................................................................................................... 15

1. Ham lay mau.................................................................................................... 15

2. S dung ham lay mau ...................................................................................... 16

3. Pho cua tn hieu lay mau ................................................................................. 17

4. Lien he gia pho cua tn hieu lien tuc va tn hieu ri rac ............................. 17

5. Chuoi xung n v ............................................................................................ 18

II. Cac phep toan tuyen tnh bat bien .............................................................................. 19

1. Tnh nhan qua .................................................................................................. 20

2. Phng trnh sai phan ....................................................................................... 21

3. Bien oi Z cua phep toan LTI ......................................................................... 21

4. Ham truyen trong mien tan so cua phep toan LTI ......................................... 23

5. Lien he gia bien oi Z va bien oi Fourier .................................................. 23

III. Loc so ...................................................................................................................... 24

1. nh ngha ........................................................................................................ 24

2. Cac bo loc ly tng .......................................................................................... 26

3. Bo loc thc te ................................................................................................... 28

4. Bo loc FIR va IIR............................................................................................. 29

IV. Bien oi Fourier ri rac ............................................................................................... 30

1. Dang DFT ......................................................................................................... 30

2. Tnh chat cua DFT ........................................................................................... 31

3. Pho cong suat ................................................................................................... 31

4. Pho trung bnh .................................................................................................. 32

5. Bien oi Fourier nhanh .................................................................................... 33

V. Bien oi Fourier thi gian ngan STFT ..................................................................... 34

1. Cong thc bien oi........................................................................................... 35

MUC LUC GVHD: PHAN NGUYEN PHUC QUOC

LUAN VAN TOT NGHIEP - iv - SVTH: HA THUC PHUNG

2. Mot so ham ca so dung trong STFT .............................................................. 36

VI. Xac suat va qua trnh ngau nhien ............................................................................... 38

1. C s xac suat .................................................................................................. 39

2. Bien ngau nhien ............................................................................................... 40

3. Ky vong, phng sai ........................................................................................ 40

VII. Tom tat ...................................................................................................................... 41

Chng 3: TRCH AC TRNG TIENG NOI .................................................................. 42

I. Ham nang lng thi gian ngan .................................................................................. 42

II. Phat hien iem au, iem cuoi cua mot t ................................................................ 42

III. Tien nhan (Pre-emphasis) ........................................................................................... 45

IV. Trch ac trng(Mel-scale Frequency Cepstral Coefficient) .................................... 46

1. Ca so hoa ....................................................................................................... 48

2. Bien oi Fourier ri rac ................................................................................... 49

3. Loc qua bo loc Mel-scale ................................................................................ 49

4. Tnh log nang lng pho .................................................................................. 51

5. Bien oi Fourier ngc .................................................................................... 51

V. Tom tat ...................................................................................................................... 52

Chng 4: LNG T VECTOR ........................................................................................ 53

I. Cac yeu to khi to chc VQ .......................................................................................... 53

II. Tap huan luyen VQ ..................................................................................................... 54

III. o o meo .................................................................................................................... 54

IV. Phan nhom cac vector huan luyen .............................................................................. 54

1. Giai thuat cum thong tin (Cluster Algorithm) ................................................. 55

2. Giai thuat Binary Split ..................................................................................... 57

V. Phan lp vector ............................................................................................................ 58

VI. Nhan dang bang VQ .................................................................................................... 59

VII. Tom tat ...................................................................................................................... 60

Chng 5: MO HNH MARKOV AN (HIDDEN MARKOV MODEL) ........................... 61

I. Khai niem ..................................................................................................................... 61

1. Chuoi Markov .................................................................................................. 61

2. Cac v du .......................................................................................................... 62

3. Mo hnh Markov an ......................................................................................... 64

II. Cac thanh phan cua HMM .......................................................................................... 64

III. Ba bai toan c ban cua HMM ..................................................................................... 66

1. Bai toan 1 ......................................................................................................... 67

2. Bai toan 2 ......................................................................................................... 71

3. Bai toan 3 ......................................................................................................... 75

IV. Phan loai mo hnh Markov an ..................................................................................... 77

V. Van e t le khi to chc mo hnh Markov an .............................................................. 78

VI. a quan