Color image encoding method and apparatus

36 Pages·2013·1.86 MB·Tagalog

US005909505A
Ulllted States Patent [19] [11] Patent Number: 5,909,505
Katayama et al. [45] Date of Patent: *Jun. 1, 1999
[54] COLOR IMAGE ENCODING METHOD AND 4,688,031 8/1987 Haggerty ............................... .. 358/459
APPARATUS 4,878,155 10/1989 Katayama et al. .................... .. 358/443
4,887,1 1 12/1989 Wataya .
[75] Inventors: Akihiro Katayama, Kawasaki; gisthihara ....................... .. 358/426
. . _ . , , a ayama e a . .
?ls?siggigézihlgeo 4,958,238 9/1990 Katayama et al. .................... .. 358/456
_> g ’ 4,974,071 11/1990 Maeda ............... .. .. 358/539
U°hl°>Y°k°hama> an of Japan 451,975,786 12/1990 Katayama et a}. .................... .. 358/459
_ _ _ _ ,008,9 0 4/1991 Katayama et a. .
[73] Asslgneei Canon Kabushlkl Kalsha, Tokyo, 5,010,580 4/1991 Vincent et a1. ....................... .. 382/163
Japan 5,014,328 5/1991 Rudak ........... .. .. 382/163
5,068,746 11/1991 Ohsawa et al. ....................... .. 358/443
[ * ] Notice: This patent is subject to a terminal dis- 5,086,484 2/1992 Katayama et al. .
claimer. 5,089,014 2/1992 Holfert.
5,089,844 2/1992 Sakai ....................................... .. 355/27
[21] AppL NO‘: 08/811’286 5,267,333 11/1993 Aono et al. .
[22] Filed: Man 4’ 1997 FOREIGN PATENT DOCUMENTS
_ _ 0163841 12/1985 European Pat. Off. .
Related U-S- Applleatlnn Data 0238027 9/1987 European Pat. on. .
0283715 9/1988 European Pat. Off. .
[62] Division of application No. 08/289,225, Aug. 12, 1994, Pat. 62-82723 4/1987 Japan .
No. 5,668,646, which is a division of application No. 2-65372 3/1990 Japan,
08/l~73,86~3, Dec. 23, 1993, Pat. No. 5,361,147, Which is a 03192876 8/1991 Japan _
ggglillélglgilgn of application No. 07/651,030, Feb. 5, 1991, 2163026 2/1986 United Kingdom _
[30] Foreign Application Priority Data OTHER PUBLICATIONS
Feb. 6, 1990 [JP] Japan .................................... .. 227658 “Image Coding Techniques For 64 Kbit/s Channels”, K.
Jun. 5, 1990 [JP] Japan GrotZ, et al., Symposium Record Broadcast Sessions 16th
Jun. 5, 1990 [JP] Japan Int’l Symposium, System Session P—2, HDTV Production:
SeP- 30: 1990 F1? Japan ~~ Today and Tomorrow, Jun. 17—22, 1989, pp. 387—409.
Sep. 30, 1990 JP Japan .................................. .. 2-262799
[51] Int. cif ............................ .. G06K 9/34- G06K 9/46- Primary Examiner_sc°“ Rogers
’ H04N U64; Attorney, Agent, or Firm—FitZpatrick, Cella, Harper &
[52] US. Cl. ........................ .. 382/164; 382/176; 382/166; Sumo
382/239; 358/539; 358/462 [57] ABSTRACT
[58] Field of Search ................................... .. 382/164, 176, _ _ _ _ _
382/239, 244, 245, 246, 247, 163; 358539, This invention relates to an image processing apparatus
530, 515, 462, 426, 427, 2611, 2612, having a function of encoding or decoding image data and
430 discloses a technique for extracting an image feature, espe
cially a thin image portion of a speci?c color of an image,
[56] References Ci- ted an d f_o r_ en_ co d‘i n g t h et in ii ma g e P ortii on W_ iit h hi1 gh e ?Tc'i enc y
to minimize degradation of image quality by selecting an
US PATENT DOCUMENTS appropriate encoding method.
4,369,461 1/1983 Tamura ................................. .. 358/500
4,446,484 5/1984 Powell . 21 Claims, 21 Drawing Sheets
33021 EDGE 30542 BINARY ARITH #306
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UNIT “VERSE UNIT
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CONVERSION UNIT
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U.S. Patent Jun. 1,1999 Sheet 2 0f 21 5,909,505
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U.S. Patent Jun. 1,1999 Sheet 3 0f 21 5,909,505
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U.S. Patent 5,909,505
Jun. 1, 1999 Sheet 4 0f 21
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U.S. Patent Jun. 1,1999 Sheet 6 0f 21 5,909,505
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U.S. Patent Jun. 1,1999 Sheet 7 0f 21 5,909,505
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U.S. Patent Jun. 1,1999 Sheet 8 0f 21 5,909,505
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U.S. Patent
Jun. 1, 1999 Sheet 9 0f 21 5,909,505
FIG. 72A FIG. 728
f (F) “
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