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

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  • 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