1 ??????? ?????? DIGITAL

1
???????? ???????

• ???????

2
1 ??????? ?????? DIGITAL

• ?? ????? ???????? ??????? Digital ??? ?????
  ???????? ?????????? (??? ????? ????? ?????? ??
  ???? ??????? ??????) ?????? ??????? ??????? ??
  ???? ??? ????? ????? ??????? ?????? (Samples) ??
  ??? ???????? ?????????? ??? ??? ????? ??????
  ????? ?? ????? ?? ????? ? ?????? (0.1) ???? ??
  ?????? ???? ??? ??? ??????? ???????? ??????
  ?????? ??? ??????? ?? ?????? ?????? ?????
  ????????? ?????? ??? ?? ????? ????? ?????? ?????
  ??? ??? ????? ??? ??????? ???????? ?????????? ???
  ??????? ??????? ?? ????? ???? ????????? ?? ????
  ???????? ?? ??????? ?????????

3
????? ??????? ??????

• ????? ??? ???? ??????? ?????? ???? ????? ??????
  ?????? ?? ??????? ????????
• ?????? ??????? ?????? ??????? Direct access ???
  ?? ??? ?? ????????? ? ??????? ?????? ??????
  ??????? ?????? ?????? ???? ???? ???? ????? ??
  ????? ????? ?? ??? ??? ???? ? ??????? ?????? ???
  ????? ??????? ?????? ??????? ??????? ???????? ???
  ???????? ??????? ????? ?????? ?????? ?? ????
  ??????? ??? ???? ???????? ???????? ?? ?????????
  ?? ???????? ??? ?????? ?????? ?? ??????.

4

• (i) ?????? ??????
• ??????? ???????? ?????? ??????? ?? ??????? ?????
  ?? ???? ?? ???? ?? ?????? ????????? ???? ??????
  ????????? ??? ??????? ???? ????? ?? ???????
  ?????? ????? ?????? ???????. ??????? ?????
  ??????? ????????? ??? ??? ?????????? ?? ?? ????
  ?????? ?????? ?????? ??????? ??? ?? ??? ???? ???
  ??? ?????? ????? ??? ??????? ???? ??? ?????. ???
  ??????? Ram ? ??????? ?????? ?? ?????????
  ??????? ??? ??? ????????? ??? ?? ????? ?????
  ????? ??????? ??? ?? ??? ???????.

5

• ??????? ????? ???? ?????? ??????? ??? ?????????
  ???? ??????? ??? ?? ??? ?? ??????? ?????? ???
  ??????? ????? ??? ????????? ??? ?? ??? ????? ??
  ??? ????? ??? ??? ????? ???? ?????? ??? ?????
  ???? ?????? ?? ?????.

6

• ??????? ??? ?????? ????? ??? ???????? ????? ??
  ????? ????? ???????? ??? ????? ??????? (??
  ??????)? ??? ??? ??? ???????? ????? ????? (??
  ????). ??? ?? ???????? ????? ?????? ????????
  ???????? ????? ??????? ?????? ?????? ??? ?? ?????
  ????? ??? ???? ?? ????? ?? ??? ????? ???????
  ?????? ?????? ????? ?? ??????? ??????? ????
  ????? ?? ?????? ???????. ?????? ?? ??? ??? ??????
  ?? ???? ??? ?????? ?? ???? ?????? ?????? ?????
  ???? ?????? ???? ??????? ?? ????? ???????? ???
  ???? ????? ????. ??? ??? ????? ?????? ????????
  ???? ????? ??? ????? ??? ????? ???? ??? ???? ??
  ????? ???? ????? ?? ??? ????? ???? ?????? ???
  ????? ??????? ??????? ???? ???? ? ?????? ??????
  ???? ????? ??? ???? ?????.

7

• ??????? ?? ?????? ??????? ???? ?????? ??????
  ??????? ?????????? ???? ?????????? ??????? ????
  ?????? ???? ??????? ??????? ????????? ????
  ??????? ???? ??? ??????? ?? ???? ??????? ???
  ?????? ??????? ?? ???????. ??????? ?? ?? ????
  ???? ???? ?? ??? ?????? ?? ??? ?????? ?????
  ?????? ???? ??? ????? ????? ??????? ??? ??? ????
  ??????? ?????? ??????? ???? ???????. ???? ??? ??
  ??? ?? ????? ????? ?????? ???????? ??? ????
  ?????? ?????? ?? ????? ?????. ????? ????? ??????
  ????? ?????? ??????? ??? ????? ??? ?? ?????
  ????????? ??? ?? ????? ??????? ???? ???? ?? ?????
  ????? ???????????? ????? ??????? ??? ?????
  ?????????? ???????.. ??? ??? ??? ???.

8

• ?????? ??????? ??????? ??? ?????? ????? ???????
  ?????? ?? ????? ????? ???????? Frames ? ???????
  Clips ????? ?? ??? ?????? ????? ??? ?? ?????
  ???????? ????????? ? ?????????? ????????. ??????
  ?? ?????? ????????? ????? ?? ????? ????????? ???
  ???????? ????? ?? ???? ?? ??????? ?????
  ????????? ???? ?????? ????. ????? ????? ??????
  ?????? ???????? ?????? ???????? ?????????? ???
  ?????? ???? ???????? ????????? ?? ??? ????????
  ???????? ????? ?????? ?????? ??????? ?????????
  ???? ???? ?????? ??????? ??????.

9

• (iii) ?????? ??????? ??????? ?????? ??????? ???
  ?????? Compression ?????? ????????? ????????
  ???? ???? ????????? ????? ?? ????? ?????
  Decompression ?? ??? ??? ??????? ???? ??????
  ?????? ????? ?? ???? ?? ??????? ????? ?????
  ?????.
• ???? ????? ?? ?????? ?????? ??? ????? ???????
  ????? ????? ??????? ??? ?????? ????? ???????
  ???????? ??? ???? ????? ?????? ????????? ???????
  ????.

10

• ???? ?????? ??????? ????????? ???? ??? ?? ??????
  ????? ?? ?? ???? ?????? ????? ??????? VCR. ?????
  ??? ???????? ??? ????? ???? ???? ????? ???? ???
  ???? ?????? CPU ?? ?????????. ?????? ?? ??????
  ??????? ???????? ?????? ?? ?? ???????? ??????? ?
  ???????? ????????? ?? ??????? ????????? ???? ??
  ?????? ????? ????? ???? ?????. ??? ???? ????????
  ???? ???? ??????/ ???? A/D Converter ??????
  ???????? ????????? ??????? ??? ????? ?? ???????
  ???????? ??????? ?? ??? ?? ????? ????? ???
  ??????? ???????? ???? ????? ???????? ?????????
  ??? ??????? ??? ????? ????? ???? ???? ?????? ???
  ??????? Sampling . ????? ?? ????? ???? ???
  ???????? ????? ???? ?????? ?????? ??? ???
  ???????.

11
2. ????? ????? -

• ???? ????? ????? ??????? ??????? ????????
• ?????? ????? ?????? ??????? ???? ???? ???? ?
  ??????? ????? ??? ??? ???????? ?? ???? ???????
  ??? ???? ???????? ???????? ????????? ????? ?????
  ????? ??? ???? ???? ???? ?? ??????. ???? ?????
  ????????? ???? ??? ??? ????? ??????? ???? ??? ???
  1 200 ???????? ?????? ??? JPEG ?? MPEG . ??????
  ????? ???? ??? ?????? ???????? ???? ???? ????????
  ?????? ?????? ???? ??? ???????? ??? ?????. ????
  ???? ????? ????? ??? ????? ?? ??????

12

• ????? ??????? ?????? ????? ?????. ??? ???? ??????
  ????? ???? ??????? ????????? ???? ?? ????? ??
  ????? ?????? ???? ???? ????? ??????? ???? ?????
  ???? ???? ????? ??????? ???????? ??? QUICK Time
  ?? VIDEO for Windows . ????? ??? ???????? ??
  ??????? ??? ??????? ??????? ??? ???? ?????????
  ??? ????? ????? ???? ?????? ?????? ?????? ?? ???
  ???? ????? ????? ??????? ?? ???? ???????
  ????????. ??? ??? ??? ????? ?? ?? ???? ?????
  ????? ????? ?????? ??????? ????? ?????? ??????
  ???? ??????? ??? ???? ???? ????.

13

• ?????? ??? ????????? Compression Standards
• ??? ?? ????? ?????? ?? ??? ????? ???? ???????
  ?????? ????? ??? (p64,DVI and C-CUNE, JPEG,
  MPEG) ?????? ?????? ????? JPEG ? MPEG ????????
  ??????? (ISCRETE COSINE TRANSFORM (DCT ??? ?????
  ???? ???? ????? ??????? ??? ?????? ????? ???????
  ? ?????.
• ?????? ????? ?????? ?????

14
?????? ????? ?????? ?????

• (i) JPEG
• ??? ??????? ??? ?? ??? JOINT PHOTOGRAPHIC EXPERTS
  GROUP ???? ???????? ???DCT ????????? ??? ?????
  ??? ?????? ?????? ???????. ???? ?????? ??? ?????
  88 ????. ???? ???64 ???? ??????? (???? ???
  ?????) ?????? ???? ??? ????? ?????? ???? ???
  ??????? ??????? ??????. ????? ????? ??????? ????
  ??????? ??? ????? ?? 64 ???? ? ??? ???? ?????
  ??????? ???? ?? ??? ????.
• ?????? ???JPEG ???? ?????? ?? ????? ????? ???????
  ????? ????? 201 ??? ?? ????? ?????? ???????.
  ??? ???? ???? 1/3 ???? ????? ???? ???????? ????
  ??? ???? ?????????.

15

• (ii) MPEG
• ??? ??????? ?? ???MOVING PICTURE EXPERTS GROUP
  ??????? ?? ????? ????? ????????. ??? ???? ????
  ????? ??? ?? ????? ???? ????? ???? ????? ????? ??
  ????? ??????. ???? ????? ???MPEG ???????? ?????
  ????? ????? 1.2 ??? 1.5 ???????? ?? ???????. ????
  ???? ????? ???CD ?? ????? ????? ??????? ???????
  ???????? ??????? ????? 30 ???? ?? ???????. ???
  ???? ????? 501 ??? ?? ???? ?????? ?????? ???
  ???? ?????? ??? ?????? ????? ??? 2001 ??? ????
  ???? ??????? ?????? ?? ??????.

16

• iii) P64
• (????? ?? ????? 64) ??? ????? VIDEO TELEPHONE
  CONFERENCING STANDARD FOR COMPRESSION ????
  ?????? ? ?????? ????? ???? ????? ???? ???????
  ???????? ??? ??? ?? ??? ??? INTERNATIONAL
  TELEGRAPH AND TELEPHONE CONSLTATIVE COMMITTEE
  (CCITT) . ??? ??? ????? ????? ???CCITT ???
  H.261 ?????? ??? ???? MULTIPLEXING ?????? ????
  DEMULTIPLEXING ????? ????????? ????????? ???????
  ??????? ??? ?????? ??????? BANDWIDTH ??????
  ???????? ????????. ?????? ?????? ???????? ???????
  ?????? ????? ??????? ??????? ?? ????? ????????
  ??? ????? ?????? ?????? ??? ??????? ???????? ??
  ????? ??????? ???????

17

• ???? ???P64 ????? ???????? ? ????? ???????? ???
  ????? ?????? ???????? ?? ????? ??????? ???????
  ????? 30 ???? ?? ??????? ???? ???? ??? 40 ??????
  ?? ??????? ??? 4 ?????? ?? ???????.

18

• (iv) DVI
• ?? ????? ????? ?????? ????? (????? ????? ?????)
  ????? ??????? ????? ??? ????? ???? 1750. ???
  ????? ????? ??? ?????? ?????? VERY LARGE SCALE
  INTGRATED (VLSI) ???? ????? ?????? ?????? ??????
  ?????.
• ???? DVI ??????? ?? ????? ?????? ????? ??? ?????
  ????? ??????? Production level video (PLV)
  ?????? ????? ??????? (Real time video - RTV) .
  ???PLV ????? ????? ???????? ?????? ????? ???????
  ???????? ??????? ?????? ????? ????? ?????? ????
  ?? ??? ????? ?? ?????.

19

• ???? ???RTV ???? ?????? ????????? ?? ??????
  ??????? ????? ???????? ????? ?????. ?? ?? ???PLV
  ? ???RTV ?????? ?????? ????? ?????? .
• ?????? ????????? DVI ?? ???? ??? ??????? ???????
  ??? 80 1 ? 160 1 ???? ???DVI ??????? ??????
  ?????? ?????? ? ??????? ????? 30 ?? ??????? ?????
  ???? ???JPEG ???? ?????? ?? ????? ??? ????? ???
  ???? ?????????. ??? ???? ????? ???DVI ????? ????
  ????? ???? ?????????? ??? ?????? ??? ???? ???????
  ???? ?????.