02-Изображения-1

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02. 2.1. ( ) 2.2. 2.3. 2.4. 2.5. 2.6. 2.7.

1. ( -) . (pixel - picture element) - . 16 256 .

1. ( -)1.1 RGB (Red, Green, Blue)

RGB32(RGBA) -8 , -8 , -8 , 8 RGB24 -8 , -8 , -8 RGB16(565 555) -5 , -6 5 , -5

1.1 RGB (Red, Green, Blue)

1.1 RGB (Red, Green, Blue) - , RGB ( additivus, ). : , , , , . , RGB , . , , , , , . . . . , , , . , . - . , , . , , ?

1. ( -)1.2 HSB (Hue, Saturation, Brightness). HSV (Hue, Saturation, Value)., , .

- , . - , . . . . , . . , . . , - .

1.2 HSB (Hue, Saturation, Brightness). HSV (Hue, Saturation, Value) HSV . , . HSB . HSB . - , , . HSB . , , . . , , HSB. HSB RGB, , .

1.2 HSB (Hue, Saturation, Brightness). HSV (Hue, Saturation, Value)1.2 RGB HSV : (R,G,B) 0 1

. : :

If MAX = MIN (i.e. S = 0), then H is undefined. If MAX = 0 (i.e. if V = 0), then S is undefined. : (,S,V) 0 (H mod 360) 360 , 0 S 1 , 0 V1

1. ( -)1.3 CMYK (Cyan, Magenta, Yellow, blacK , , , ).

1.3 CMYK (Cyan, Magenta, Yellow, blacK ) . , . ? , . . , , . , , , , , . , , .

1.3 CMYK (Cyan, Magenta, Yellow, blacK ) , , - , . , , () - CMY. CMY ( ) CMYK. (Black) , (Blue). . , , 0 ( ) 100 ( ). -, . , . , CMYK.

1.3 CMYK (Cyan, Magenta, Yellow, blacK )1.3 RGB CMYK

1. ( -)1.4 YIQ (Y luminance, I - intermodulation (In-phase), Q quadrature ).Y luminance, luminosity, luma - I - Q - Chrominance,Chroma -

1.4 YIQ (Y luminance, I - intermodulation (In-phase), Q - quadrature ).

1.4 YIQ (Y luminance, I - intermodulation (In-phase), Q - quadrature ).YIQ NTSC. - . YIQ RGBY= 0.299*R + 0.587*G + 0.114*B I = 0.596*R 0.275*G 0.321*B Q= 0.212*R 0.523*G + 0.311*B R = Y + 0.956*I + 0.621*Q G = Y 0.272*I 0.647*Q B = Y 1.107*I + 1.704*Q

1. ( -)1.5 YCrCb (Y luminance, Cr - Chroma-red, Cb Chroma-Blue ).Y luminance, luminosity, luma - Cr Cb Chrominance,Chroma -

1.5 YCrCb (Y luminance, Cr - Chroma-red, Cb Chroma-Blue ).

1.5 YCrCb (Y luminance, Cr - Chroma-red, Cb Chroma-Blue ).YCrCb PAL SECAM. - -. YIQ 33 .

YCrCb RGBY = 0.299R + 0.587G + 0.114B Cr = k1(R - Y) Cb = k2(B - Y) k1 k2 Cr = 0.5*R + ... Cb = 0.5*B + ... Cr = 0.5R - 0.419G' - 0.081B Cb = - 0.169R - 0.331G + 0.5B : (Y,Cr,Cb) 0 Y 1 , -0.5 Cr 0.5 , -0.5 Cr 0.5

1. ( -)1.5 YUVY luminance, luminosity, luma - V U YUV RGB Y = 0.299R + 0.587G + 0.114B U = 0.492(B - Y) V = 0.877 (R - Y) U = 0.147R 0.289G + 0.436B V = 0.615R 0.515G 0.100B Chrominance,Chroma -

R = Y + 1.140V G = Y 0.395U 0.581V B = Y + 2.032U

1.5 YUV YUV (chroma subsampling )

4:4:4

Y0 U0 V0 Y1 U1 V1 Y2 U2 V2 Y3 U3 V3

[Y0 U0 V0] [Y1 U1 V1] [Y2 U2 V2] [Y3 U3 V3]

4:2:24:1:1

Y0 U0 Y1 V1 Y2 U2 Y3 V3Y0 U0 Y1 Y2 V2 Y34:4:4 4:2:2 YUV YUV YUV YUV YU YU YU YU YV YV YV YV YU YU YU YU

[Y0 U0 V1] [Y1 U0 V1] [Y2 U2 V3] [Y3 U2 V3][Y0 U0 V2] [Y1 U0 V2] [Y2 U0 V2] [Y3 U0 V2]4:2:0 YV YV YV YV YU Y YU Y YV Y YV Y YU Y YU Y YV Y YV Y

YUV YUV YUV YUV

YUV YUV YUV YUV

YUV YUV YUV YUV

1.5 YUV

4:4:4 High-end (postproduction) 4:2:2 high-end ( ). : Digital Betacam, CCIR 601 / Serial Digital Interface 4:1:1 lower-end and consumer applications. . : NTSC DV ..

4:2:0 . : PAL DV, DVD, MPEG 2

1. ( -)1.6 LAB (L*a*b).L luminance, luminosity, luma - b

1.5 Lab 1931 , Lab (L*a*b). , HSB, RGB CMYK. . L (Lightness) - . - . b - . , , , . Photoshop Lab. : Lab .

1. (4-16) , . . : , , .. 2. , . : , . 3. . : . 4. . : .

2.

3.

1. . : .2. ( ). : CD-ROM. . 3. . : WWW

4. 1. . 2. . . 3. . . 4. . , . 5. . . 6. ( ), . 7. . . 8. . 9. . 10. . .

5.

. : D S. D, , .

5.1

. (BMP, TGA, RAS...) .

5.1 , . .

5.2 , S ( ) D, D . : . NxN, N:

N=3. N=1, .

5.3 , , D , : (D[i], D[i+1], D[i+f]), . 3x3 .12 3 28 29

65 4 27 26

78 9 22 23

1211 10 21 20

1314 15 16 17

30

25

24

19

18

5.4 N-ro - . - , . , - , , (1) . , M=N=2, : 1 13 2 14 3 15 4 1625 37 26 38 27 39 28 40

59

17 6

18 7

19 8

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29 41 30 42 31 43 32 44 21 10 22 11 23 12 24 33 45 34 46 35 47 36 48

MxN, , , : , , , , .

5.5 , - , :

36 - 1, 12 - 2.

5.5 , 1: 1 29 28 27 26 22 21 312 3 4 5 6 8 7 9 30 25 23 20 32 24 19 33 18 34 13 14 17 35

10 11 12 15 16 36

, 2.

5.6 , , , , . :

, , ( 9, 10, 14...), 180 . ( 45...48) , () .

5.7 (-) , . , :1 3 4 10 11 2 5 9 12 20 6 8 13 19 21 7 14 18 22 27 15 17 23 26 28 16 24 25 29 30

JPEG ( 8x8 ).

5.8 . , 2x2 :

1 2

4 3

1 4

2 3

( ) , - , ( ), - ; , ; .

5.8 ( ) , - , ( ), - ; , ; .