3
: LZW .
1. ʲ Ͳ ²Ҳ
1.1. .
. ' , , , . , ' , , . ' . ' .
, , , , .
( ) ? , , , , , . , .
, .
:
1) , ;
2) , , , ( - ). , , .
:
- (. Lempel, Ziv), - , "" - . - (, , );
(. Huffman), , ' .
(ARJ, RAR, ZIP ) ' - LZH.
. , : RLE (Run Length Encoding); KWE (KeyWord Encoding); ; LZ78 (LZW, MW, AP, Y)
RLE , , , . KWE . , . . ϳ . , . , .
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, : (), (JPEG) (MPEG). , , ( 5:1).
LZW.
³ ( ), . : - . ֳ . . LZW. , . .
abbacbbcac
1
| 1 = A | |||
| 2 = B | |||
| 3 = C | |||
| A | B | 4 = AB | |
| B | B | 5 = BB | |
| B | A | 6 = BA | |
| A | C | 7 = AC | |
| C | B | 8 = CB | |
| B | B | ||
| BB | C | 9 = BBC | |
| C | A | 10 = CA | |
| A | C | ||
| AC |
: 1 2 2 1 3 5 3 7
: 1 2 2 1 3 5 3 7
2
| 1 = A | ||||
| 2 = B | ||||
| 3 = C | ||||
| A | A | |||
| B | B | 4 = AB | ||
| B | B | 5 = BB | ||
| A | A | 6 = BA | ||
| C | C | 7 = AC | ||
| B | BB | 8 = CB | ||
| C | C | 9 = BBC | ||
| A | AC | 10 = CA | ||
: A B B A C B B C A C
2.
1. LZW.
2.
3.
3. ²
1. LZW.
2. .
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LZW. .
-41
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-42
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| 10 | Բ |
| 11 | Ͳ |
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