?a???s?as? 12?

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?a???s?as? 12?
??f?a?? ?pe?e??as?a ?a? ?????s? ?????a?

• Te???a ???µat?? ?a? ?pe?e??as?a ?????µ?? ???????

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??sa???? (1)

• ?? ???µa e??a? ??a? p??? s?µa?t???? pa?????ta?
  pe????af??, p?? s???? ap???ste?e? ?at? p??? t??
  d?ad??as?a a?a?????s?? a?t??e?µ???? ?a? t??
  e?a???? pe??????.
• ?? ?????p?? µp????? ?a d?a??????? ?????de?
  d?af??et???? ap????se?? ?a? e?t?se?? ???µ?t??,
  e?? ap? t?? ap????se?? t?? ???? µ??? 20-30.
• ?e??p?? t? 65 t?? a?s??t???? st? a????p??? µ?t?
  e??a? e?a?s??t?? st? ???????, 33 st? p??s??? ?a?
  µ??? t? 2 st? µp?e.

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??sa???? (2)

• ? epe?e??as?a ?????µ?? ??f?a??? e????a?,
  ?????eta? se d?? µe???e? ?at?????e?
• ?pe?e??as?a e?????? p?????? ???µat?? se a?t? t??
  ?at?????a e?t?ss??ta? e????e? p?? ?aµß????ta? ap?
  a?s??t??e? p?????? ???µat??.
• ?e?d????µat?sµ?? e?????? ed? ? st???? e??a? ?
  a???es? ???µat?? se e????e? ep?p?d?? t?? ????.

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?as??? ?a?a?t???st??? ???µat?? (1)

• ??t???ß???a (Radiance)e??a? t? s??????? p?s?
  e????e?a? p?? e?p?µpeta? ap? t?? p??? f?t??.
  ?et??ta? se Watts.
• F?te???t?ta (Luminance)e??a? µ?a e?t?µ?s? t??
  p?s?? t?? e????e?a? p?? ft??e? st?? pa?at???t?.
  ?et??ta? se lumens (lm).
• ?aµp??t?ta (Brightness)e??a? ??a? ?p??e?µe?????
  pa?????ta?. ?µpe????e? t? st???e?? t??
  f?te???t?ta? (Intensity), p?? e??a? ? a???µat????
  pa?????ta?. ?a ep?peda t?? ???? e??a? ???µa?a
  µ?t??s?? t?? ??tas??.

pe????af? f?te???? p????
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?as??? ?a?a?t???st??? ???µat?? (2)

• ?p????s? (?????) (Hue)a?t?p??s?pe?e? t?
  ep???at?ste?? ???µa ?ts? ?p?? t? a?t??aµß??eta? ?
  pa?at???t??.
• ?a?a??t?ta (???esµ??) (Saturation)a?af??eta?
  st?? ?a?a??t?ta t?? ???µat??, se s??s? µe t? p?s?
  ?sp??? f?t?? µe t? ?p??? a?aµe????eta?.
• ?aµp??t?ta (Brightness)e??a? ??a? ?p??e?µe?????
  pa?????ta?. ?µpe????e? t? st???e?? t??
  f?te???t?ta? (Intensity), p?? e??a? ? a???µat????
  pa?????ta?. ?a ep?peda t?? ???? e??a? ???µa?a
  µ?t??s?? t?? ??tas??.

pe????af? ???µat??
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Te???a ???µat?? (1)

• ?as??? (primary) ???µata
• ??????? (Red)
• ???s??? (Green)
• ?p?e (Blue)
• S?µp????µat??? (secondary) ???µata
• ??a?? (Cyan)
• ??ß (Magenta)
• ??t???? (Yellow)

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Te???a ???µat?? (2)
?as??? ???µata
S?µp????µat??? ???µata
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Te???a ???µat?? (3)

• ?? ???µat??? d????aµµa p??t????e ap? t?? CIE
  (xR, yG).
• zB, z1-(xy)
• ???e s?µe?? sta ???a t?? d?a???µµat?? e??a?
  ap???ta ?a?a?? ???µa, e?? ?s? p??????µe p??? t?
  s?µe?? t?? ?s?? e????e?a? (?sp??) ? ?a?a??t?ta
  µe???eta?.
• ??? e??s??µe µe e??e?a ??aµµ? d?? s?µe?a t??
  d?a???µµat??, t?te ???e s?µe?? t?? ??aµµ??
  a?t?st???e? se µ?a ???sµ??? µ??? t?? ???µ?t?? p??
  ß??s???ta? sta ???a t??.
• ??t?st???a ?s????? ?a? ??a t? t?????? p??
  s??µat??eta? a? e??s??µe t??a s?µe?a (µ??? t??
  t???? ???µ?t??)

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???µat??? µ??t??a \ RGB (1)

• St? RGB µ??t???, ta ???µata ?e?????ta? p??sµ??e??
  t?? ßas???? ???µ?t?? ???????, ???s???, ?p?e.
• ?? µ??t??? ßas??eta? st? ?a?tes?a?? s?st?µa ?a?
  a?apa??st?ta? µe t?? RGB ??ß?.
• ???s?µ?p??e?ta? st?? ape?????s? ???µ?t?? st??
  ????e? ?a? ?e???? sta s?st?µata ape?????s??.

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???µat??? µ??t??a \ RGB (2)

• ???e e????a ap?te?e?ta? ap? 3 ?p?-e????e?, µ?a
  ??a ???e ßas??? ???µa.

???????
???s???
?p?e
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???µat??? µ??t??a \ CMY CMYK (1)

• St? CMY µ??t???, ta ???µata ?e?????ta? p??sµ??e??
  t?? s?µp????µat???? ???µ?t?? ??a??, ??ß, ??t????.
• ?? µ??t??? a?t? e??a? a?t?st???? µe t? RGB ?a?
  ???s?µ?p??e?ta? st?? ?????µ? e?t?p?s?. St?? p????
  p??st??eta? ep?p???? t? µa??? ???µa ??a ?a??te?a
  ?pt??? ap?te??sµata.

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???µat??? µ??t??a \ CMY CMYK (2)

• ???e e????a ap?te?e?ta? ap? 4 ?p?-e????e?.

??a??
??ß
??t????
?a???
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???µat??? µ??t??a \ CMY CMYK (3)

• ? µetat??p? µeta?? t?? d?? µ??t???? ???eta? ??
  e???

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???µat??? µ??t??a \ HSI (1)

• St? HSI µ??t???, ta ???µata a?apa??st??ta? ap?
  d?? ???µat????? pa?????te? (Hue Saturation) ?a?
  t?? f?te???t?t? (Intensity).
• ???s?µ?p??e?ta? ??a t?? pe????af? t?? ???µ?t?? µe
  ß?s? t?? a????p??? a?t?????.

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???µat??? µ??t??a \ HSI (2)

• ??a p?a?t??? ?pt??? a?apa??stas? ??a t? HS?
  s?st?µa, ep?t?????eta? e?? pe??st?????µe t?? RGB
  ??ß? ?ts? ?ste st?? ???et? ????a ?a ß??s?eta? ?
  e??e?a p?? e???e? t?? ????e? t?? µa???? ?a? t??
  ?sp???.

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???µat??? µ??t??a \ HSI (3)

• ???e e????a ap?te?e?ta? ap? 3 ?p?-e????e?, µ?a
  ??a ???e s???st?sa.

?p????s?
?a?a??t?ta
??tas?
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???µat??? µ??t??a \ HSI (4)

• ?etat??p?? µeta?? t?? µ??t????
• RGB?HSI

??a t?? a?t?st??f? µetat??p? a?at???te st? ß?ß??? Digital Image Processing, R.C. Gonzalez, R.E. Woods , Addison-Wesley, 2002
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??apa??stas? t?? ???µat???? a?t??????

• ? a?s??s? t?? ???µat?? ?fe??eta? sta
  ????a t?? aµf?ß??st??e?d??? ta ?p??a e??a? t????
  e?d?? µe f?sµata ap????f?s?? S1(?), S2(?) ?a?
  S3(?) st?? pe?????? ??t????-p??s???, p??s???
  ?a? µp?e a?t?st???a.
• ?? ap????se?? t?? ?????? se f?? µe ???µat???
  pe??e??µe?? C(?) d????ta? ??
• ?d?e? fasµat???? ap????se?? a?(C) s?µa?????
  a?t????? ?d??? ???µat?? (a??µ? ?? a? st??
  p?a?µat???t?ta p???e?ta? ??a d?af??et??? C(?) )

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??apa?a???? ???µat?? (1)

• Te????µe t?e?? ßas???? p???? f?t?? µe fasµat???
  pe??e??µe?? Pk(?) , k1,2,3 ?a? e????e?a ?s? µe
  1 ? ???e µ?a.
• G?a ?a s????s??µe ??a ???µa a?aµ??????µe ta
  Pk(?) µe ?at?????e? a?a????e? ßk . ??te ?
  ?p???es? p?? p????pte? ?a ???eta? a?t???pt? ??
  C(?) , d??ad?

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??apa?a???? ???µat?? (2)

• ? ap????s? t?? i-?st?? e?d??? ?????? st?? f?te???
  p??? t?p?? k e??a?
• ?p?te p????pt??? ?? ???st?? ?? color matching
  equations
• G?a ded?µ??a C(?), Pk(?) ?a? Si(?), ??
  ??t??µe?e? a?a????e? a??µ???? ßk (t?????µat????
  s??te?est??) ß??s???ta? µe ??s? s?st?µat??
• G?a ?a ?p???e? ??s? ?a? ?a e??a? ap?de?t? p??pe?
  ? p??a?a? ?a e??a? a?t?st????µ?? ?a? ta ßk ?a
  e??a? µ? a???t???

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?pe?e??as?e? \ ?e?d????µat?sµ?? (1)

• ?e?d????µat?sµ?? ???µ??eta? ? epe?e??as?a e????a?
  ?at? t?? ?p??a a?a??t??ta? ???µata se t?µ?? t??
  ????, s?µf??a µe ??p??? p???a????sµ??? ???t????.

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?pe?e??as?e? \ ?e?d????µat?sµ?? (2)

• ?eµa??sµ?? ??tas??
• ?st? ta ep?peda t?? ????. ??????µe
  ?at?f??a, ?a? a?a??t??µe
  ???µata s?µf??a µe t?? , ?ta?
  

?eµa??sµ?? µe ??a ?at?f??
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?pe?e??as?e? \ ?e?d????µat?sµ?? (3)

• ?etat??p? ep?p?d?? t?? ???? se ???µata
• ??te???µe 3 a?e???t?t??? µetas??µat?sµ??? st??
  asp??µa??? e????a ?a? a?a??t??µe ta ap?te??sµata
  st?? 3 s???st?se? µ?a? RGB e????a?.

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?pe?e??as?e? ???s?s? ?st????µµat?? (1)

• ?at? t?? e??s?s? ?st????µµat??, st???? µa? e??a?
  ? ?µ???µ??f? ?ata??µ? t?? e?t?se??. ?at? s???pe?a
  e??a? p??t?µ?te?? ?a ???s?µ?p???s??µe t? HIS
  s?st?µa ?a? ?a µetas??µat?s??µe t?? I s???st?sa.

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?pe?e??as?e? ???s?s? ?st????µµat?? (2)
?????? ?a? e??s?µ??? e????a
? s???st?sa ??tas?? t?? e??????
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?pe?e??as?e? ???s?s? ?st????µµat?? (3)

• ???s?s? ?st????µµat?? µp??e? ?a ???e? ?a? st? RGB
  s?st?µa, e?? epe?e??ast??µe ?e????st? t?? ???e
  s???st?sa. Se a?t? t?? pe??pt?s? ?µ??, e?t?? ap?
  t?? f?te???t?ta ep??e????ta? ?a? ta ???µata.