() . , , , . . ( Forward Error Control) . , (Feedback or Backward Error Control), . , .
, . , . . .
d ( ), . d min. r = ent(d min1)/2 d min1 ( ent ). , dmin=2 . d min=3. L =log2 K , , L . L - (.. 2) , 1.
1. 100110, .. = 6. , L = 3
010 # 011 # 110= 111,
# , 000. . . ( ), , . , 100010, 010 # 110 = 100, .. 011, .
2. 1100000, 110 ( 110 # 111 =001). 1101000, 010, 100, .. .
, , , (CRC Cyclic Redundance Code). , , , .
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g (), a g (). , . , .
, Xn1, Xn n- , n . , n =10 =2, Xn1=1023=1193, g (X) = 11 1011, Ai g (X) Ai . 2.2.
, , , : 1) , , ; 2) (2 ) , , Ȕ; 3) CRC K - , , ..
. , .
3. = 1001 1101, 11001.
= 4, (2 )=100111010000. . 2.7.
. 2.7.
.
:
g (X) = Xl6 + l2 + 5+ 1,
1 0001 0000 0010 0001.
, .. . , . :
= n / q,
n ( ); q , . , n . .
, , , .
, , () .
, ASCII, , , 10 , , .
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RLE (Run Length Encoding). . , .
, , . - .
() ,
Ar Ap > d,
, ; r ; d ( ).
. 2.8. . ( d), , . . 2.8 t1, t2, t4, t7. , .
. 2.8.
MPEG (Moving Pictures Experts Group) ( ). , , . MPEG .
JPEG (Joint Photographic Expert Group), ( , ). , , , , .
, , , .
, . , , . . , : , . .
, . , , .
, . , .
, . . , , 1 0.
, LZ- ( ). LZ- : , , , . . .
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