<????(Source Coding)> ?5? ????? ????

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lt????(Source Coding)gt?5? ????? ????

• ?? ? ????? Source Coding
• Markov ??? Huffman Coding
• ??? Run-length Coding System
• DPCM, ADPCM, DM, ADM
• Gray Code Anti-Gray Code

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??? ????? ????
ltHuffman Codegt? ??? ???? ??? ?????? ???? ?? ?
?? ??? ???? ??
lt??? ????? ??gt ? Markov chain? ??? Huffman
Coding - ??? ???? ?? (? q ??? ??
??? ??? u ??.)? Run-length Coding System
- 0 run-length? ???? ???? ?? -
??(image)??? ??? ?? ??? Sample? ????? ???
?????? - DPCM(differential pulse code
modulation) - ADPCM(adaptive DPCM) -
DM(delta modulation) - ADM(adaptive DM)
ltA/D, D/A ??, ??? ?? ?? ???? ????gt? Gray Code
?? ??? ?? ?? 1-bit ? ?? (A/D, D/A ??) ?
Anti-Gray Code ?? ??? ?? ??? ?? bits ?? (memory
addressing)
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Markov ??? Huffman Code

• jth order Markov process (j-memory source) P(si
  si1, si2, ., sij), for all i 1, 2, , q
  i1, i2, , ij ? j-memory ?? ?
  ????? S s1, s2, , sq? ???

? of states (j-memory) q j
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Markov ??? ??? Huffman Coding(?)

• ???? 1

• ???? 2 ????(transition matrix)

• ???? 3 ???(transition graph)

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Markov ??? ??? Huffman Coding(?)

• ???(present state)? ??

• ????(next state)? ??

• ?????(the state after next state)? ??

• Sequence of Matrix

lt??gt1. ?? n? ????? ?? ??? ???? ???2. ???
?(row)? ??? 13. ?? q?q matrix (1-memory source)
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• ????(equilibrium state)? ?? ???? ????? ???
  ???? ??

• Matrix equation???? ?? 3?? ???? ????
• Matrix equation???? 2?? ???? ??? ????, ???
  1?? ???? Pa Pb Pc 1? ??
• 3? 1? ?????? ?? ???? ??? ???

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Markov ??? ??? Huffman Coding(?)
? ?????? ??? Huffman ??
Si Pi b 4/11 c 4/11 a
3/11
1
7/11
0
00
4/11
1
01
? ??????(Markov)
? ??????(Huffman)
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??? Run-length Coding ???
? ??? ???(predictive encoder)

• ???? ????? En? 0-run? ???
• Sn random sequence
• En ?? 0, ?? 1

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??? Run-length Coding ???(??)
? ??? ???(predictive decoder)

• ???? ??? ?????? ??? ???
• ?? ????? ??? ???? ???? En? ??? ????.
• ??? ???? ????? ?? sequence? ???

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??? Run-length Coding ???(??)
? Run-length ???
En? 0-run length?? k-bit ????? ???
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??? Run-length Coding ???(??)
? Run-length ???
??? ?? ??? k-bit ??????? En? ??
k-bit block decoder
En
Run-length
k-bit block code
Binary gen.

• ltAlgorithmgt
• Run-length 0 ? ?? ? En 1
• Run-length 1 2k-2 ? ?? ? En 00
  01 ????
• Run-length 2k-1 ? ?? ? En 00 0

2k-1?
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Run-length Coding? ???? ??
lt?? ??? ?? kgt
lt???? ??gt
?? ?? bit ? (run-length coder)
run-length1 ? ??(?? ??)

???()
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??????? ???? ??
? PCM (pulse code modulation) -
???(sampling), ???(quantizing), ???(coding)
- ??? ??? ????? ???
? DPCM (differential pulse code modulation) -
??? ??, ??? ???? ??(difference)?? ???
? ADPCM (adaptive differential pulse code
modulation) - DPCM ???? ??? step? ?????
????
? DM (delta modulation) - ???? ???? 1-bit
???? ?? (1-bit DPCM)

• ADM (adaptive delta modulation) - DM ???? ???
  ???? ?? ??? step? ??? ????

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DPCM(differential PCM)
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DM(delta modulation)
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DM? ??? ADM

• Granular Noise ????? ??? ??? ??? ??? ??? ? ?
  ?? ???? ??
• Overload Noise ????? ??? ??? ??? ??? ??? ??
  ??? ???? ??

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Gray Code
?? ??? ?? ??? 1-bit? ????? ??? Code ?? -
Magnetic disk? ????(sector ) ?? - Linear
quantization
1-bit gray 2-bit gray 3-bit gray 4-bit gray
0 0 0 0 0 0
0 0 0 0 1
0 1 0 0 1
0 0 0 1
1 1 0 1 1
0 0 1 1
1 0 0 1 0
0 0 1 0
1 1
0 0 1 1 0

1 1 1 0 1 1 1

1 0 1 0 1 0 1

1 0 0 0 1 0 0

1 1 0
0

1 1 0 1

1 1 1 1

1 1 1 0

1 0 1 0

1 0 1 1

1 0 0 1

1 0 0
0
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(Gray ? Pure Binary) ?? ??

• ???? ??? ????? ????.

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Anti-Gray Code
?? ??? ?? ??? ?? bit? ???? ??? Code ?? -
????? ?? ??(address code) ??
ltn-bit Anti-Gray Code? ??gt 1) (n-1)-bit Gray
Code 2) Attaching leading 0 3)
Interpolations of the complement codes