1. , , DWT, .
2. , DWT, , , .
3. DWT , . .
DWT- , , : . . .
, ( ) .
DWT DWT :
x[n] n. (Haar Low Pass Filter) :
g[n] = 1/2 * (x[n] + x[n+1])
(Haar High Pass Filter) :
h[n] = 1/2 * (x[n+1] - x[n])
, :
x[n] = g[n] - h[n] x[n+1] = g[n] + h[n]
g[n] h[n] . , , x[n] . , . , x[n] : g[0], g[2], g[4],.... h[0], h[2], h[4],.....
x[0] = g[0] - h[0]
x[1] = g[0] + h[0] x[2] = g[2] - h[2] x[3] = g[2] + h[2] ...
. , , . . , , . ( ) (base layer), - (enhancement layer). h[n] , , , , x[n]. , . , . , wavelet-.
. . ( ) . () .
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, x[n] 8- . g[n] 8 , h[n] , 4. , , . , . , h[n].
g[n] g[n-1] . g[n] , , g[n-1], , .
, , : Cinepak
1. , , .
2. , .
, . , , . , .
, , : MPEG-1,2 4.
1. .
2. .
3. , : MPEG, H.261 H.263.
4. .
. , , , , . , , ( ), . . ( ) 16x16 , () . , , , . , . MPEG B- (bi-directionally predicted) .