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7 . . (1). 2- D 3-D - PowerPoint PPT Presentation

Transcript

• 7

• (1) 2-D 3-D

• (2) 3 : gray levels (.. Huffman)

pixel (interpixel) ( )- ( )

• (3) :

- (.., ADPCM) - (.., DCT, Wavelet) - (.., fractals)

• (4) 1 - - -

(codebook)

• (5) : HuffmanBit plane codingConstant Area Coding Contour Tracing LZW ... : ( )

• Huffman (1) x bits/pixel. p(i) . : . . : H(B) .

• Huffman (2)

Huffman

1.0

0.57

0.43

0.27

0.17

0.07

0.04

0.30

0.26

0.15

0.12

0.10

0.03

0.02

0.02

i=2

i=1

i=3

i=0

i=4

i=5

i=6

i=7

1.0

0.57

0.43

0.27

0.17

0.07

0.04

0.30

0.26

0.15

0.12

0.10

0.03

0.02

0.02

i=2

i=1

i=3

i=0

i=4

i=5

i=6

i=7

• xi pixels. k , , :

, .

, Huffman .

• Read . . . READ 3 , , 2 , .

• LZW (1) - (TIFF, GIF). bits. bits.

• LZW (2) 256 0...255. #257 Clear code #258 EOI. bits . bits .

0

255Clear codeEOIstring

string

• - Bit plane coding L Constant Area Coding , (0, 10, 11). Contour Tracing

• (1) , pixel . pixel (x,y) . pixel.

• (2) pixel , . .

:

• (3)

+

-

en

n

n

+

+

n

en

n

• (4) . . ( ).

• (5)

en

+

-

n

n

en

+

+

n

+

-

n

en

n

• (1) .

, . ( ) .

• (2) (DFT, DCT, WHT, DST, Wavelet) blocks (8x8, 16x16) bits

• DCT

• DCT DFT

• DCT

8764321076543210654331104433210033321100221110001110000000000000

DCT

bits block 8x8 bits

1111100011110000111000001100000010000000000000000000000000000000

1101100011110000110000001001000001000000010000000000000000000000

• DCT: block DCT (: , ) : block IDCT block

• (1)

126:151:128:115:18:14:1

• (2)

126:151:128:115:18:14:1