US2014029848A1PendingUtilityA1
Re-coloring a color image
Est. expiryAug 31, 2026(~0.1 yrs left)· nominal 20-yr term from priority
Inventors:Bruce J. Lindbloom
G06T 11/10G06T 11/001
50
PatentIndex Score
0
Cited by
0
References
0
Claims
Abstract
Technology for re-coloring a region of a color image including determining an original base color in a region of a color image; establishing at least one shading parameter in the region of the color image; and combining a new base color with the at least one shading parameter in the region of the color image thereby producing a re-colored region of the color image.
Claims
exact text as granted — not AI-modifiedWhat is claimed is:
1 . A method for re-coloring a color image comprising:
determining an original base color in a predetermined region of the color image by implementing an ambient/diffuse shading model using a processing unit; establishing at least one shading parameter in the predetermined region of the color image by implementing the ambient/diffuse shading model using the processing unit; retrieving a texture map comprising a plurality of base colors and a pattern defining the spatial distribution of the plurality of base colors; and combining the texture map with the at least one shading parameter for the predetermined region of the color image thereby producing a re-colored predetermined region of the color image using the processing unit having the pattern applied across the region of the color image.
2 . The method according to claim 1 wherein,
the ambient/diffuse shading model is implemented according to:
E total =E base (1 +k diffuse(Cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, or
E total =E light E base ( k ambient +k difuse cos θ)
which under the assumptions
E light =1
k ambient +k diffuse =1
simplifies to
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, or
E i =E base (1 +k diffuse (cos θ i− 1))
where E is the energy relationship of light and color in the energy domain, E i is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, and where i represents a pixel within the region, θi being the angle formed at pixel i, or
E c,i =E c,base ( i+k diffuse (COS θ i −1))
where E is the energy relationship of light and color in the energy domain, E c,i is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, where i represents a pixel within the region, θ i being the angle formed at pixel i. and where the subscript c indicates a color channel, or
E total =E base ( i+k diffuse (COS θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein the base color E base is the original base color and is determined by identifying the maximum color of the region, where the surface normal is pointing directly toward the light source so that θ=0 and cos θ=1, and:
E
base
=
E
maximum
1
+
k
diffuse
(
cos
(
0
)
-
1
)
=
E
maximum
,
or
E
total
=
E
base
(
1
+
k
diffuse
(
cos
θ
-
1
)
)
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein the diffuse coefficient k diffuse is determined by identifying the minimum color of the region, where the surface normal is pointing away from the light source so that θ=π/2 and cos θ=0, and:
E minimum =E base (1 +k diffuse (cos(π/2)−1))
from which k diffuse is solved:
k diffuse =( E base −E minimum )/ E base , or
E i =E base (1 +k diffuse (cos θ i −1))
where E is the energy relationship of light and color in the energy domain, E i is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, and where i represents a pixel within the region, θ i being the angle formed at pixel i; and,
wherein for each pixel i in the region, the value for cos θ i is computed from the shading model:
E i =E base (1 +k diffuse (cos θ i −1))
which may be solved for cos θ i and simplified to:
cos θ i =( E i −E minimum )/( E base −E minimum ), or
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein a new base color, E base ′ is substituted into the shading equation for each pixel in the region, producing a re-colored second region:
E total ′=E base ′(1 +k diffuse (cos θ−1))
where the prime, ″ refers to the new base color, as opposed to the original base color.
3 . The method according to claim 1 wherein,
determining the original base color is performed by converting the predetermined region of the color image to a predetermined color space comprising a plurality of color channels; and
establishing and combining are performed upon the predetermined region for each color channel of the plurality of color channels.
4 . The method according to claim 1 wherein,
the texture map is obtained using a synthesis procedure executed by the processing unit.
5 . The method according to claim 1 wherein,
the original base color is colorless.
6 . The method according to claim 1 wherein,
each color in the plurality of colors within the texture map are defined in a predetermined color space by a set of neutral values.
7 . The method according to claim 1 wherein,
establishing at least one shading parameter comprises establishing the at least one shading parameter for a color component of a predetermined color space representation of the colors in the predetermined region showing the largest variation within the predetermined region.
8 . A method for re-coloring a color image comprising:
determining a base color in a first predetermined region of the color image by implementing an ambient/diffuse shading model using a processing unit; establishing at least one shading parameter in a second predetermined region of the color image by implementing the ambient/diffuse shading model using the processing unit; generating a new second predetermined region of the color image by combining the at least one shading parameter for the second predetermined region of the color image with the base color.
9 . The method according to claim 8 wherein,
the ambient/diffuse shading model is implemented according to:
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, or
E total =E light E base ( k ambient +k diffuse cos θ)
which under the assumptions
E light =1
k ambient +k diffuse =1
simplifies to
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, or
E i =E base (1 +k diffuse (cos θ i −1))
where E is the energy relationship of light and color in the energy domain, E i is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, and where i represents a pixel within the region, θi being the angle formed at pixel i, or
E c,i =E c,base (1 +k diffuse (cos θ i −1))
where E is the energy relationship of light and color in the energy domain, E c,i is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, where i represents a pixel within the region, θ i being the angle formed at pixel i. and where the subscript C indicates a color channel, or
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein the base color E base is the original base color and is determined by identifying the maximum color of the region, where the surface normal is pointing directly toward the light source so that θ=0 and cos θ=1, and:
E
base
=
E
maximum
1
+
k
diffuse
(
cos
(
0
)
-
1
)
=
E
maximum
,
or
E
total
=
E
base
(
1
+
k
diffuse
(
cos
θ
-
1
)
)
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein the diffuse coefficient k diffuse is determined by identifying the minimum color of the region, where the surface normal is pointing away from the light source so that θ=π/2 and cos θ=0, and:
E minimum =E base (1 +k diffuse (cos(π/2)−1))
from which k diffuse is solved:
k diffuse =( E base −E minimum )/ E base , or
E i =E base (1 +k diffuse (cos θ i −1))
where E is the energy relationship of light and color in the energy domain, E i is the total color, E base represents the base color, the term k diffuse (cos θ i −1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, and where i represents a pixel within the region, θ i being the angle formed at pixel i; and,
wherein for each pixel i in the region, the value for cos is computed from the shading model:
E i =E base (1 +k diffuse (cos θ i −1))
which may be solved for cos θ i and simplified to:
cos θ i =( E i −E minimum )/( E base −E minimum ), or
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein a new base color, E base′ is substituted into the shading equation for each pixel in the region, producing a re-colored second region:
E total ′=E base ′(1 +k diffuse (cos θ−1))
where the prime, ″ refers to the new base color, as opposed to the original base color.
10 . The method according to claim 8 wherein,
determining the base color is performed by converting the first predetermined region of the color image to a predetermined color space comprising a plurality of color channels; and
establishing and combining are performed upon the second predetermined region for each color channel of the plurality of color channels.
11 . The method according to claim 8 wherein,
the first and second predetermined regions of the image are the same region.
12 . The method according to claim 8 wherein,
the base color is colorless.
13 . The method according to claim 8 wherein,
establishing at least one shading parameter comprises establishing the at least one shading parameter for a color component of a predetermined color space representation of the colors in the second predetermined region showing the largest variation within the second predetermined region.
14 . The method according to claim 8 further comprising;
determining an original base color for the second predetermined region of the color image by implementing the ambient/diffuse shading model using the processing unit;
identifying a third predetermined regions of the color image having the same original base color as the first predetermined region using the ambient/diffuse shading model and the processing unit;
establishing at least one shading parameter in the third predetermined region of the color image by implementing the ambient/diffuse shading model using the processing unit;
generating a new third predetermined region of the color image by combining the at least one shading parameter for the third predetermined region of the color image with a new base color.
15 . A method for re-coloring a color image comprising:
determining a base color in a predetermined region of the color image by implementing an ambient/diffuse shading model using a processing unit; establishing at least one shading parameter in the predetermined region of the color image by implementing the ambient/diffuse shading model using the processing unit; generating a new predetermined region of the color image by either combining the at least one shading parameter for the predetermined region of the color image with a new base color defined in a predetermined color space by a set of neutral values or not adding a new base color into an energy equation associated with the ambient/diffuse shading model when combining the new base color with the at least one shading parameter for the predetermined region of the color image.
16 . The method according to claim 15 wherein,
the ambient/diffuse shading model is implemented according to:
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, or
E total =E light E base ( k ambient +k diffuse cos θ)
which under the assumptions
E light =1
k ambient +k diffuse =1
simplifies to
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, or
E i =E base (1 +k diffuse (cos θ i −1))
where E is the energy relationship of light and color in the energy domain, E i is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, and where i represents a pixel within the region, θ i being the angle formed at pixel i, or
E c,i =E c,base (1 +k diffuse (cos θ i −1))
where E is the energy relationship of light and color in the energy domain, E c,i is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, where i represents a pixel within the region, θ i being the angle formed at pixel i. and where the subscript C indicates a color channel, or
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein the base color E base is the original base color and is determined by identifying the maximum color of the region, where the surface normal is pointing directly toward the light source so that θ=0 and cos θ=1, and:
E
base
=
E
maximum
1
+
k
diffuse
(
cos
(
0
)
-
1
)
=
E
maximum
,
or
E
total
=
E
base
(
1
+
k
diffuse
(
cos
θ
-
1
)
)
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein the diffuse coefficient k diffuse is determined by identifying the minimum color of the region, where the surface normal is pointing away from the light source so that θ=π/2 and cos θ=0, and:
E minimum =E base (1 +k diffuse (cos(π/2)−1))
from which k diffuse is solved:
k diffuse =( E base −E minimum )/ E base , or
E i =E base (1 +k diffuse (cos θ i −1))
where E is the energy relationship of light and color in the energy domain, E, is the total color, E base represents the base color, the term k diffuse (COS θ i −1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image, and where i represents a pixel within the region, θ i being the angle formed at pixel i; and,
wherein for each pixel i in the region, the value for cos θ i is computed from the shading model:
E i =E base (1 +k diffuse (cos θ i −1))
which may be solved for cos O and simplified to:
cos θ i ( E i −E minimum )/( E base −E minimum ), or
E total =E base (1 +k diffuse (cos θ−1))
where E is the energy relationship of light and color in the energy domain, E total is the total color, E base represents the base color, the term k diffuse (cos θ−1) represents the at least one shading parameter and θ is the angle formed between a surface normal in the region and a corresponding vector pointing toward a light source in the image; and,
wherein a new base color, E base ′ is substituted into the shading equation for each pixel in the region, producing a re-colored second region:
E total ′=E base ′(1 +k diffuse (cos θ−1))
where the prime, ′, refers to the new base color, as opposed to the original base color.
17 . The method according to claim 15 wherein,
determining the base color is performed by converting the predetermined region of the color image to a predetermined color space comprising a plurality of color channels; and
establishing and combining are performed upon the predetermined region for each color channel of the plurality of color channels.
18 . The method according to claim 15 wherein,
the base color is colorless.
19 . The method according to claim 15 wherein,
establishing at least one shading parameter comprises establishing the at least one shading parameter for a color component of a predetermined color space representation of the colors in the predetermined region showing the largest variation within the predetermined region.
20 . The method according to claim 15 further comprising;
determining a plurality of other regions of the color Image by implementing the ambient/diffuse shading model using the processing unit;
establishing for each other region of the plurality of other regions at least one shading parameter by implementing the ambient/diffuse shading model using the processing unit; and
generating for each other region of the plurality of other regions a new other region of the color image by either combining the at least one shading parameter for that other region of the plurality of other regions with a new base color defined in a predetermined color space by a set of neutral values or not adding a new base color into an energy equation associated with the ambient/diffuse shading model when combining the new base color with the at least one shading parameter for the predetermined region of the color image.Join the waitlist — get patent alerts
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