US5666436A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for transforming a source image to an output image
Assignee: Electronics for Imaging Inc
•
Filing: 1995-04-17
•
Granted: 1997-09-09
•
Expires: 2015-04-17
Abstract
Abstract The present invention is a method and apparatus for transforming source images to output images. It performs color transformations using a lookup table and a hashing circuit for referencing entries in the lookup table. The index generated by the hashing circuit is dependent on a first color value. A color encoding circuit is coupled to the lookup table for generating an encoded color value dependent on the first color value. The index produced by the hashing circuit is further dependent upon response characteristics of the human eye. The hashing circuit generates indexes referencing widely separated entries in the plurality of entries of the lookup table when first color values have small differences in value. A comparing circuit is coupled to the lookup table and the color encoding circuit for comparing the entry of the lookup table and the encoded color value to determine a match. A color calculation circuit is coupled to the lookup table for generating a second color value dependent on the first color value. The color calculation circuit generates the second color value when a match does not occur. The second color value is also stored in the entry of the lookup table. When a match does occur, the lookup table outputs the second color value instead of calculating a new second color value. In the preferred embodiment of the present invention, the hashing circuit comprises a plurality of lookup tables and a logic circuit coupled to the plurality of lookup tables for generating the index.
Inventors
- 👤 Andrew Eames
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 04:46
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/6016; H04N1/6022; H04N1/6025
Claims Analysis
Total Claims: 96
Claim 1
Independent Claim
240 words
An apparatus for transforming a source image to an output image comprising: a first lookup table comprising a plurality of entries; a hashing circuit coupled to said first lookup table for receiving a source image comprising a plurality of source picture elements, and for producing an index for each source picture element of a plurality of said source picture elements dependent on a first color of said each source picture element, said index for referencing an entry of said plurality of entries of said first lookup table; an encoding circuit coupled to said first lookup table for generating an encoded color for said source picture element dependent on said first color of said each source picture element; a comparing circuit coupled to said first lookup table and said encoding circuit for comparing said entry of said first lookup table referenced by said index and said encoded color to determine a match; a calculation circuit coupled to said first lookup table for generating a second color for an output picture element corresponding to said each source picture element dependent on said first color of said each source picture element, said calculation circuit generating said second color of said output picture element and storing said second color in said entry of said first lookup table referenced by said index when a match does not occur, said first lookup table outputting said second color of said output picture element when a match occurs.
Claim 2
Independent Claim
240 words
An apparatus for transforming a source image to an output image comprising: a first lookup table comprising a plurality of entries; a hashing circuit coupled to said first lookup table for receiving a source image comprising a plurality of source picture elements, and for producing an index for each source picture element of a plurality of said source picture elements dependent on a first color of said each source picture element, said index for referencing an entry of said plurality of entries of said first lookup table; an encoding circuit coupled to said first lookup table for generating an encoded color for said source picture element dependent on said first color of said each source picture element; a comparing circuit coupled to said first lookup table and said encoding circuit for comparing said entry of said first lookup table referenced by said index and said encoded color to determine a match; a calculation circuit coupled to said first lookup table for generating a second color for an output picture element corresponding to said each source picture element dependent on said first color of said each source picture element, said calculation circuit generating said second color of said output picture element and storing said second color in said entry of said first lookup table referenced by said index when a match does not occur, said first lookup table outputting said second color of said output picture element when a match occurs.
Claim 3
Dependent Claim
16 words
The apparatus of claim 1 wherein said first color is described by P bits of data.
Claim 4
Dependent Claim
15 words
The apparatus of claim 2 wherein said index comprises N bits of data where N≦P.
Claim 5
Dependent Claim
16 words
The apparatus of claim 3 wherein said encoded color is represented by P-N bits of data.
Claim 6
Dependent Claim
17 words
The apparatus of claim 1 wherein said index is dependent upon response characteristics of the human eye.
Claim 7
Dependent Claim
33 words
The apparatus of claim 1 wherein said hashing circuit generates indexes referencing widely separated entries in said plurality of entries of said first lookup table for source picture elements having similar first colors.
Claim 8
Dependent Claim
21 words
The apparatus of claim 1 wherein said plurality of entries of said first lookup table are initialized to contain initial data.
Claim 9
Dependent Claim
57 words
The apparatus of claim 1 wherein said hashing circuit comprises: a plurality of lookup tables for storing transformed color components of a first plurality of color components, respectively, of said first color of said source picture element; and, a logic circuit coupled to said plurality of lookup tables for generating said index using said transformed color components.
Claim 10
Dependent Claim
62 words
The apparatus of claim 8 wherein said first color is an RGB color having R, G, and B color components and described by P bits of data, and wherein said plurality of lookup tables for storing transformed color components comprise second and third lookup tables each comprising 2 P/3 entries for storing transformed values of said B and R color components, respectively.
Claim 11
Dependent Claim
62 words
The apparatus of claim 8 wherein said first color is an CMYK color having C, Y and M color components and described by P bits of data, and wherein said plurality of lookup tables for storing transformed color components comprise second and third lookup tables each comprising 2 P/3 entries for storing transformed values of said M and C color components, respectively.
Claim 12
Dependent Claim
13 words
The apparatus of claim 1 wherein said first color is an appearance color.
Claim 13
Dependent Claim
13 words
The apparatus of claim 11 wherein said appearance color is a RGB color.
Claim 14
Dependent Claim
32 words
The apparatus of claim 12 wherein said index is dependent upon a G component of said RGB color to a greater extent than upon R and B components of said RGB color.
Claim 15
Dependent Claim
13 words
The apparatus of claim 1 wherein said first color is a colorant color.
Claim 16
Dependent Claim
13 words
The apparatus of claim 14 wherein said colorant color is a CMYK color.
Claim 17
Dependent Claim
32 words
The apparatus of claim 15 wherein said index is independent upon a Y component of said CMYK color to a greater extent than upon C and M components of said CMYK color.
Claim 18
Dependent Claim
13 words
The apparatus of claim 1 wherein said second color is an appearance color.
Claim 19
Dependent Claim
13 words
The apparatus of claim 1 wherein said second color is a colorant color.
Claim 20
Dependent Claim
13 words
The apparatus of claim 1 wherein said second color is an intermediate color.
Claim 21
Dependent Claim
16 words
The apparatus of claim 1 further comprising source image generation means for generating said source image.
Claim 22
Dependent Claim
14 words
The apparatus of claim 20 wherein said source image generation means comprises a scanner.
Claim 23
Dependent Claim
14 words
The apparatus of claim 20 wherein said source image generation means comprises a computer.
Claim 24
Dependent Claim
15 words
The apparatus of claim 1 further comprising image output means for receiving said output image.
Claim 25
Dependent Claim
14 words
The apparatus of claim 23 wherein said image output means comprises a color printer.
Claim 26
Dependent Claim
14 words
The apparatus of claim 23 wherein said image output means comprises a color monitor.
Claim 27
Independent Claim
197 words
A method for transforming a source image to an output image, said method comprising the steps of: obtaining a source image comprising a plurality of picture elements; generating a first lookup table comprising a plurality of entries; generating an index for each of a plurality of said source picture elements dependent on a first color of each source picture element of a plurality of said source picture elements; said index for referencing an entry of said plurality of entries in said first lookup table; generating an encoded color for said each source picture element dependent on said first color of said each source picture element; comparing said entry of said first lookup table referenced by said index and said encoded color to determine a match; obtaining a second color of an output picture element corresponding to said each source printer element from said entry referenced by said index when a match occurs; generating said second color of said output picture element dependent on said first color and storing said encoded color and said second color in said entry referenced by said index when a match does not occur; outputting an output image comprising said output picture element.
Claim 28
Independent Claim
197 words
A method for transforming a source image to an output image, said method comprising the steps of: obtaining a source image comprising a plurality of picture elements; generating a first lookup table comprising a plurality of entries; generating an index for each of a plurality of said source picture elements dependent on a first color of each source picture element of a plurality of said source picture elements; said index for referencing an entry of said plurality of entries in said first lookup table; generating an encoded color for said each source picture element dependent on said first color of said each source picture element; comparing said entry of said first lookup table referenced by said index and said encoded color to determine a match; obtaining a second color of an output picture element corresponding to said each source printer element from said entry referenced by said index when a match occurs; generating said second color of said output picture element dependent on said first color and storing said encoded color and said second color in said entry referenced by said index when a match does not occur; outputting an output image comprising said output picture element.
Claim 29
Dependent Claim
16 words
The method of claim 26 wherein said first color is described by P bits of data.
Claim 30
Dependent Claim
15 words
The method of claim 26 wherein said index comprises N bits of data where N≦P.
Claim 31
Dependent Claim
16 words
The method of claim 28 wherein said encoded color is represented by P-N bits of data.
Claim 32
Dependent Claim
17 words
The method of claim 26 wherein said index is dependent upon response characteristics of the human eye.
Claim 33
Dependent Claim
29 words
The method of claim 26 wherein indexes reference widely separated entries in said plurality of entries of said first lookup table for source picture elements having similar first colors.
Claim 34
Dependent Claim
23 words
The method of claim 26 comprising the step of initializing said plurality of entries of said first lookup table to contain initial data.
Claim 35
Dependent Claim
50 words
The method of claim 26 comprising the steps of: generating transformed color components of a first plurality of color components of said first color of said source picture element; storing said transformed color components in a plurality of lookup tables, respectively; and, generating said index using said transformed color components.
Claim 36
Dependent Claim
62 words
The method of claim 33 wherein said first color is an RGB color having R, G and B color components and described by P bits of data, and wherein said plurality of lookup tables for storing transformed color components comprise second and third lookup tables each comprising 2 P/3 entries for storing transformed values of said B and R color components, respectively.
Claim 37
Dependent Claim
62 words
The method of claim 33 wherein said first color is an CMYK color having C, Y and M color components and described by P bits of data, and wherein said plurality of lookup tables for storing transformed color components comprise second and third lookup tables each comprising 2 P/3 entries for storing transformed values of said M and C color components, respectively.
Claim 38
Dependent Claim
13 words
The method of claim 26 wherein said first color is an appearance color.
Claim 39
Dependent Claim
13 words
The method of claim 26 wherein said first color is a colorant color.
Claim 40
Dependent Claim
41 words
The method of claim 37 wherein said colorant color is a CMYK color and wherein said index is independent upon a Y component of said CMYK color to a greater extent than upon C and M components of said CMYK color.
Claim 41
Dependent Claim
13 words
The method of claim 26 wherein said second color is an appearance color.
Claim 42
Dependent Claim
13 words
The method of claim 26 wherein said second color is a colorant color.
Claim 43
Dependent Claim
13 words
The method of claim 26 wherein said first color is an RGB color.
Claim 44
Dependent Claim
32 words
The method of claim 41 wherein said index is dependent upon a G component of said RGB color to a greater extent than upon R and B components of said RGB color.
Claim 45
Dependent Claim
13 words
The method of claim 26 wherein said second color is a CMYK color.
Claim 46
Dependent Claim
13 words
The method of claim 26 wherein said second color is an intermediate color.
Claim 47
Dependent Claim
14 words
The method of claim 26 wherein said source image is obtained from a scanner.
Claim 48
Dependent Claim
13 words
The method of claim 26 wherein said source is obtained from a computer.
Claim 49
Dependent Claim
25 words
The method of claim 26 wherein said step of outputting said output image comprises the step of printing said output image using a color printer.
Claim 50
Dependent Claim
23 words
The method of claim 26 wherein said outputting said output image comprises the step of displaying said output image on a color monitor.
Claim 51
Independent Claim
171 words
An apparatus for generating and updating a first lookup table comprising a plurality of entries, each of said plurality of entries representing a color in a color space, said apparatus comprising; an encoding circuit for generating an encoded color output based upon a first color of a source picture element; a comparing circuit coupled to said lookup table and said encoding circuit for comparing an entry of said lookup table and said encoded color output of said encoding circuit to determine a match; a calculation circuit said calculation circuit coupled to said first lookup table for generating a second color for an output picture element corresponding to said source picture element dependent on said first color of said source picture element and for writing said generated second color into said entry of said first lookup table, said calculation circuit generating said second color of said output picture element when a match does not occur, said first lookup table outputting said second color of said output picture element when a match occurs.
Claim 52
Independent Claim
171 words
An apparatus for generating and updating a first lookup table comprising a plurality of entries, each of said plurality of entries representing a color in a color space, said apparatus comprising; an encoding circuit for generating an encoded color output based upon a first color of a source picture element; a comparing circuit coupled to said lookup table and said encoding circuit for comparing an entry of said lookup table and said encoded color output of said encoding circuit to determine a match; a calculation circuit said calculation circuit coupled to said first lookup table for generating a second color for an output picture element corresponding to said source picture element dependent on said first color of said source picture element and for writing said generated second color into said entry of said first lookup table, said calculation circuit generating said second color of said output picture element when a match does not occur, said first lookup table outputting said second color of said output picture element when a match occurs.
Claim 53
Dependent Claim
26 words
The apparatus of claim 49 wherein said encoding circuit receives a plurality of source picture elements, each of said source picture elements having a first color.
Claim 54
Dependent Claim
24 words
The apparatus of claim 49 further comprising an index generating circuit for generating an index for referencing said entry of said first lookup table.
Claim 55
Dependent Claim
34 words
The apparatus of claim 51 wherein said index generating circuit generates indexes referencing widely separated entries in said plurality of entries of said first lookup table for source picture elements having similar first colors.
Claim 56
Dependent Claim
21 words
The apparatus of claim 49 wherein said plurality of entries of said first lookup table are initialized to contain initial data.
Claim 57
Dependent Claim
22 words
The apparatus of claim 53 wherein each of said entry of said first lookup table is described in a CMYK color space.
Claim 58
Dependent Claim
58 words
The apparatus of claim 51 wherein said index generating circuit comprises: a plurality of lookup tables for storing transformed color components of a first plurality of color components, respectively, of said first color of said source picture element; and, a logic circuit coupled to said plurality of lookup tables for generating said index using said transformed color components.
Claim 59
Dependent Claim
62 words
The apparatus of claim 55 wherein said first color is an RGB color having R, G and B color components and described by P bits of data, and wherein said plurality of lookup tables for storing transformed color components comprise second and third lookup tables each comprising 2 P/3 entries for storing transformed values of said B and R color components, respectively.
Claim 60
Dependent Claim
62 words
The apparatus of claim 55 wherein said first color is an CMYK color having C, Y and M color components and described by P bits of data, and wherein said plurality of lookup tables for storing transformed color components comprise second and third lookup tables each comprising 2 P/3 entries for storing transformed values of said M and C color components, respectively.
Claim 61
Dependent Claim
13 words
The apparatus of claim 49 wherein said first color is an appearance color.
Claim 62
Dependent Claim
13 words
The apparatus of claim 58 wherein said appearance color is an RGB color.
Claim 63
Dependent Claim
40 words
The apparatus of claim 59 wherein an index for referencing said entry of said lookup table is dependent upon a G component of said RGB color to a greater extent than upon R and B components of said RGB color.
Claim 64
Dependent Claim
13 words
The apparatus of claim 49 wherein said first color is a colorant color.
Claim 65
Dependent Claim
13 words
The apparatus of claim 61 wherein said colorant color is a CMYK color.
Claim 66
Dependent Claim
40 words
The apparatus of claim 62 wherein an index for referencing said entry of said lookup table is dependent upon a Y component of said CMYK color to a greater extent than upon C and M components of said CMYK color.
Claim 67
Dependent Claim
13 words
The apparatus of claim 49 wherein said second color is an appearance color.
Claim 68
Dependent Claim
13 words
The apparatus of claim 49 wherein said second color is a colorant color.
Claim 69
Dependent Claim
13 words
The apparatus of claim 49 wherein said second color is an intermediate color.
Claim 70
Dependent Claim
17 words
The apparatus of claim 49 further comprising source image generation means for generating said source picture element.
Claim 71
Dependent Claim
14 words
The apparatus of claim 67 wherein said source image generation means comprises a scanner.
Claim 72
Dependent Claim
14 words
The apparatus of claim 67 wherein said source image generation means comprises a computer.
Claim 73
Dependent Claim
20 words
The apparatus of claim 49 further comprising image output means for receiving said output picture element from said processing means.
Claim 74
Dependent Claim
14 words
The apparatus of claim 70 wherein said image output means comprises a color printer.
Claim 75
Dependent Claim
14 words
The apparatus of claim 70 wherein said image output means comprises a color monitor.
Claim 76
Independent Claim
169 words
A method for transforming a source image to an output image, said method comprising the steps of: obtaining a source image comprising a plurality of source picture elements, each of said source picture elements having a first color; generating a first lookup table comprising a plurality of entries, each of said plurality of entries representing a color in a color space; generating an encoded color for each source picture element of a plurality of said source picture elements dependent on said first color of said each source picture element; comparing an entry of said first lookup table and said encoded color to determine a match; obtaining a second color of an output picture element corresponding to said source picture element from said entry when a match occurs; generating said second color of said output picture element dependent on said first color and writing said second color into said entry of said first lookup table when a match does not occur; outputting an output image comprising said output picture element.
Claim 77
Independent Claim
169 words
A method for transforming a source image to an output image, said method comprising the steps of: obtaining a source image comprising a plurality of source picture elements, each of said source picture elements having a first color; generating a first lookup table comprising a plurality of entries, each of said plurality of entries representing a color in a color space; generating an encoded color for each source picture element of a plurality of said source picture elements dependent on said first color of said each source picture element; comparing an entry of said first lookup table and said encoded color to determine a match; obtaining a second color of an output picture element corresponding to said source picture element from said entry when a match occurs; generating said second color of said output picture element dependent on said first color and writing said second color into said entry of said first lookup table when a match does not occur; outputting an output image comprising said output picture element.
Claim 78
Dependent Claim
33 words
The method of claim 73 further comprising the step of generating an index for referencing said entry of said first lookup table based on said first color of said each source picture element.
Claim 79
Dependent Claim
49 words
The method of claim 74 comprising the steps of: generating transformed color components of a first plurality of color components of said first color of said source picture element; storing said transformed color components in a plurality of lookup tables; and, generating said index using said transformed color components.
Claim 80
Dependent Claim
62 words
The method of claim 75 wherein said first color is an RGB color having R, G and B color components and described by P bits of data, and wherein said plurality of lookup tables for storing transformed color components comprise second and third lookup tables each comprising 2 P/3 entries for storing transformed values of said B and R color components, respectively.
Claim 81
Dependent Claim
51 words
The method of claim 75 wherein said first color is an CMYK color having C, Y and M color components and described by P bits of data, and wherein said plurality of lookup tables for storing transformed color entries for storing transformed values of said M and C color components, respectively.
Claim 82
Dependent Claim
13 words
The method of claim 74 wherein said first color is an colorant color.
Claim 83
Dependent Claim
41 words
The method of claim 78 wherein said colorant color is a CMYK color and wherein said index is dependent upon a Y component of said CMYK color to a greater extent than upon C and M components of said CMYK color.
Claim 84
Dependent Claim
13 words
The method of claim 74 wherein said first color is an RGB color.
Claim 85
Dependent Claim
32 words
The method of claim 80 wherein said index is dependent upon a G component of said RGB color to a greater extent than upon R and B components of said RGB color.
Claim 86
Dependent Claim
23 words
The method of claim 73 comprising the step of initializing said plurality of entries of said first lookup table to contain initial data.
Claim 87
Dependent Claim
22 words
The apparatus of claim 82 wherein each of said entries of said first lookup table is described in a CMYK color space.
Claim 88
Dependent Claim
13 words
The method of claim 73 wherein said first color is an appearance color.
Claim 89
Dependent Claim
13 words
The method of claim 73 wherein said second color is an appearance color.
Claim 90
Dependent Claim
13 words
The method of claim 73 wherein said second color is an colorant color.
Claim 91
Dependent Claim
13 words
The method of claim 73 wherein said second color is a CMYK color.
Claim 92
Dependent Claim
13 words
The method of claim 73 wherein said second color is an intermediate color.
Claim 93
Dependent Claim
14 words
The method of claim 73 wherein said source image is obtained from a scanner.
Claim 94
Dependent Claim
14 words
The method of claim 73 wherein said source image is obtained from a computer.
Claim 95
Dependent Claim
25 words
The method of claim 73 wherein said step of outputting said output image comprises the step of printing said output image using a color printer.
Claim 96
Dependent Claim
23 words
The method of claim 3 wherein said outputting said output image comprises the step of displaying said output image on a color monitor.
References Cited (Backward Citations)
US4477833A
Cited
US4717954A
Cited
US4901258A
Cited
US5068644A
Cited
US5323248A
Cited
US5241373A
Cited
US5278678A
Cited
US5315415A
Cited
US5283671A
Cited
US5343311A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-09-08 | 2001-03-10 | 2001-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-09-08 | 2005-03-10 | 2005-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-09-08 | 2009-03-10 | 2009-09-09 | $7700.00 | Window Closed / Lapsed |