Capitolul 1: Bancuri de filtre
Capitolul 1: Bancuri de filtre
Capitolul 1: Bancuri de filtre
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PAS cap. 1: <strong>Bancuri</strong> <strong>de</strong> <strong>filtre</strong> – p. 25/75<br />
Exemplu<br />
[<br />
3<br />
• Luăm A(z) =<br />
4 z−1 − 1 8 (1 + z−2 1<br />
)<br />
4 (1 + z−1 )<br />
− 1 4 (1 + z−1 1<br />
)<br />
2<br />
[<br />
]<br />
1 − 1<br />
S(z) =<br />
2 (1 + z−1 )<br />
1<br />
2 (1 + z−1 3<br />
)<br />
2 z−1 − 1 4 (1 + z−2 )<br />
• Rezultă S(z)A(z) = z −1 I, <strong>de</strong>ci se obţine RP cu D = 3<br />
• Filtrele corespunzătoare sunt<br />
H 0 (z) = 3 4 z−2 − 1 8 (1 + z−4 ) + 1 4 z−1 (1 + z −2 ) = (− 1 8 , 1 4 , 3 4 , 1 4 , −1 8 )<br />
H 1 (z) = − 1 4 (1 + z−2 ) + 1 2 z−1 = (− 1 4 , 1 2 , −1 4 )<br />
F 0 (z) = z −1 + 1 2 (1 + z−2 ) = ( 1 2 ,1, 1 2 )<br />
F 1 (z) = − 1 2 z−1 (1 + z −2 ) + 3 2 z−2 − 1 4 (1 + z−4 ) = (− 1 4 , −1 2 , 3 2 , −1 2 , −1 8 )<br />
• Acestea sunt <strong>filtre</strong>le 5/3 (LeGall) din JPEG2000<br />
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