Patent US6912313B2 successfully refreshed from Google Patents.
US6912313B2
Expired / Lapsed
US
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Image background replacement method
Assignee: Rakuten Group Inc
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Filing: 2001-05-31
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Granted: 2005-06-28
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Expires: 2021-05-31
Abstract
Abstract An image's pixels are initially segmented into pixels of the image foreground and background by comparing the pixels of the image to updated models of background reference pixels. Pixel structures are identified in the image. The probability that a pixel is in the background or foreground is refined by considering the initial segmentation of the pixel's neighbors and the pixel's membership in a pixel structure. If a pixel is identified as a background pixel it is replaced by a pixel of a new background.
Inventors
- 👤 Baoxin Li
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:01
CPC Classifications
G; G06; G06T; G06T11/00; H; H04; H04N; H04N1/00; H04N1/387; H04N1/3871
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
83 words
A method of image processing comprising the steps of: (a) determining a probability that an input pixel is one of a background and a foreground pixel of said image by comparing said input pixel to a background reference pixel model; and (b) revising said probability for said input pixel according to a probability that a neighboring pixel is a pixel of one of said background and said foreground and a relationship of said input pixel and a pixel structure included in said image.
Claim 2
Independent Claim
83 words
A method of image processing comprising the steps of: (a) determining a probability that an input pixel is one of a background and a foreground pixel of said image by comparing said input pixel to a background reference pixel model; and (b) revising said probability for said input pixel according to a probability that a neighboring pixel is a pixel of one of said background and said foreground and a relationship of said input pixel and a pixel structure included in said image.
Claim 3
Dependent Claim
128 words
The method of claim 1 wherein the step of determining a probability that an input pixel is one of a background and a foreground pixel of said image by comparing said input pixel to a model of a background reference pixel comprises the steps of: (a) comparing a difference between said input pixel and said background reference pixel model to a threshold difference; (b) determining said probability that said input pixel is one of said background and said foreground pixels from a first probability function if said difference at least equals said threshold difference; and (c) determining said probability that said input pixel is one of said background and said foreground pixels from a second probability function if said difference does not at least equal said threshold difference.
Claim 4
Dependent Claim
35 words
The method of claim 2 wherein said difference between said input pixel and said background reference pixel model comprises a difference in a chromatic value of said input pixel and said background reference pixel model.
Claim 5
Dependent Claim
12 words
The method of claim 2 wherein said threshold comprises a chromatic value.
Claim 6
Dependent Claim
149 words
The method of claim 1 wherein the step of revising said probability for said input pixel according to a probability that a neighboring pixel is a pixel of one of said background and said foreground and a relationship of said input pixel and a pixel structure included in said image comprises the steps of: (a) filtering said image to identify a pixel structure included in said image; (b) assigning a first probability that a pixel neighboring said input pixel is a pixel of one of said background and said foreground as said revised probability for said input pixel, if said input pixel is included in said structure; and (c) if said input pixel is not included in said structure, assigning a second probability that a pixel neighboring said input pixel is a pixel of one of said background and said foreground as said revised probability for said input pixel.
Claim 7
Dependent Claim
32 words
The method of claim 1 wherein said background reference pixel model is a mean of a pixel of a background reference image and at least one input pixel of an image background.
Claim 8
Dependent Claim
26 words
The method of claim 1 further comprising the step of revising said background reference pixel model if said input pixel is a pixel of said background.
Claim 9
Dependent Claim
38 words
The method of claim 1 further comprising the step of substituting a new pixel for said input pixel in said image if said revised probability determines that said input pixel is more probably a pixel of said background.
Claim 10
Independent Claim
144 words
A method of processing an image comprising the steps of: (a) capturing an image comprising a plurality of input pixels representing a background and a foreground of a scene; (b) capturing a background reference image comprising a plurality of background reference pixels representing a background of said scene; (c) determining a probability that an input pixel is a pixel of one of said background and said foreground according to a relationship of said input pixel and a background reference pixel; (d) identifying a pixel structure in said image; (f) revising said probability for said input pixel according to a membership of said input pixel in said pixel structure and a probability that a neighboring pixel is a pixel of one of said background and said foreground; and (g) substituting a new background pixel for a spatially corresponding input pixel classified as a background pixel.
Claim 11
Independent Claim
144 words
A method of processing an image comprising the steps of: (a) capturing an image comprising a plurality of input pixels representing a background and a foreground of a scene; (b) capturing a background reference image comprising a plurality of background reference pixels representing a background of said scene; (c) determining a probability that an input pixel is a pixel of one of said background and said foreground according to a relationship of said input pixel and a background reference pixel; (d) identifying a pixel structure in said image; (f) revising said probability for said input pixel according to a membership of said input pixel in said pixel structure and a probability that a neighboring pixel is a pixel of one of said background and said foreground; and (g) substituting a new background pixel for a spatially corresponding input pixel classified as a background pixel.
Claim 12
Dependent Claim
121 words
The method claim 9 wherein the step of determining a probability that an input pixel is a pixel of one of said background and said foreground according to a relationship of said input pixel and a background reference pixel comprises the steps of: (a) determining a first probability that said input pixel is a pixel of one of said background and said foreground if a relationship of said input pixel and said background reference pixel at least equals a threshold; and (b) determining a second probability that said input pixel is a pixel of one of said background and said foreground if said relationship of said input pixel and said background reference pixel does not at least equal to said threshold.
Claim 13
Dependent Claim
31 words
The method of claim 10 wherein at least one of said first and said second probabilities is a function of a difference between said input pixel and said background reference pixel.
Claim 14
Dependent Claim
37 words
The method of claim 11 wherein said difference between said input pixel and said background reference pixel comprises a difference between a chromatic value of said input pixel and a chromatic value of said background reference pixel.
Claim 15
Dependent Claim
37 words
The method of claim 12 wherein at least one of said functions of said chromatic values of said input pixel and said background reference pixel comprises a sum of a plurality of chromatic components for said pixel.
Claim 16
Dependent Claim
37 words
The method of claim 10 wherein said relationship of said input pixel and said background reference pixel comprises a difference between a chromatic value of said input pixel and a chromatic value of said background reference pixel.
Claim 17
Dependent Claim
33 words
The method of claim 14 wherein at least one said chromatic values of said input pixel and said background reference pixel comprises a sum of a plurality of chromatic components for said pixel.
Claim 18
Dependent Claim
35 words
The method of claim 14 wherein said chromatic value of said background reference pixel comprises a mean of a plurality of chromatic values for a plurality of background pixels included in a plurality of images.
Claim 19
Dependent Claim
20 words
The method of claim 10 wherein said threshold comprises a function of a chromatic value for said background reference pixel.
Claim 20
Dependent Claim
40 words
The method of claim 17 wherein said function of said chromatic value of said background reference pixel comprises a function of a standard deviation of a chromatic value for a plurality of background pixels included in a plurality of images.
Claim 21
Dependent Claim
37 words
The method of claim 9 wherein the step of identifying a structure in said image comprises the step of filtering said image with a morphological filter to identify a plurality of connected input pixels in said image.
Claim 22
Dependent Claim
104 words
The method of claim 9 wherein the step of revising said probability for said input pixel according to a membership of said input pixel in said pixel structure and a probability that a neighboring pixel is a pixel of one of said background and said foreground comprises the steps of: (a) revising one of said first and said second probabilities according to a first relationship if said input pixel is a pixel included in said structure; and (b) revising one of said first and said second probabilities according to a second relationship if said input pixel is not a pixel included in said structure.
Claim 23
Dependent Claim
37 words
The method of claim 20 wherein at least one of said first and said second relationships comprises a probability that a pixel neighboring said input pixel is a pixel of one of said background and said foreground.
Claim 24
Dependent Claim
45 words
The method of claim 20 wherein at least one of said first and said second relationship comprises one of a maximum and a minimum of a probability that a pixel neighboring said input pixel is a pixel of one of said foreground and said background.
Claim 25
Dependent Claim
28 words
The method of claim 9 further comprising the step of revising a background reference pixel according to a relationship of said background reference pixel and an input pixel.
Claim 26
Dependent Claim
63 words
The method of claim 23 wherein the step of revising said background reference pixel according to a relationship of said background reference pixel and an input pixel comprises the step of determining a mean of a chromatic value of said background reference pixel and a chromatic value of said input pixel if said input pixel is classified as a pixel of said background.
Claim 27
Independent Claim
212 words
A method of replacing an image background in a video sequence comprising the steps of: (a) capturing an image comprising a plurality of input pixels representing a background and a foreground of a scene; (b) capturing a background reference image comprising a plurality of background reference pixels representing a background of said scene; (c) classifying an input pixel as a pixel of said background if a difference between said input pixel and a background reference pixel is less than a threshold difference; (d) filtering said image to identify a pixel structure included in said image; (e) revising said classification of said input pixel according to a first probability relationship if said input pixel is a pixel of said pixel structure; (f) revising said classification of said input pixel according to a second probability relationship if said input pixel is not a pixel of said pixel structure; (g) revising a background reference pixel if said revised classification of a spatially corresponding input pixel classifies said input pixel as a background pixel; (h) substituting a new background pixel for said input pixel if said input pixel is classified as a pixel of said background; and (i) capturing another image comprising a plurality of input pixels representing a background and a foreground of said scene.
Claim 28
Independent Claim
212 words
A method of replacing an image background in a video sequence comprising the steps of: (a) capturing an image comprising a plurality of input pixels representing a background and a foreground of a scene; (b) capturing a background reference image comprising a plurality of background reference pixels representing a background of said scene; (c) classifying an input pixel as a pixel of said background if a difference between said input pixel and a background reference pixel is less than a threshold difference; (d) filtering said image to identify a pixel structure included in said image; (e) revising said classification of said input pixel according to a first probability relationship if said input pixel is a pixel of said pixel structure; (f) revising said classification of said input pixel according to a second probability relationship if said input pixel is not a pixel of said pixel structure; (g) revising a background reference pixel if said revised classification of a spatially corresponding input pixel classifies said input pixel as a background pixel; (h) substituting a new background pixel for said input pixel if said input pixel is classified as a pixel of said background; and (i) capturing another image comprising a plurality of input pixels representing a background and a foreground of said scene.
Claim 29
Dependent Claim
72 words
The method of claim 25 wherein the step of classifying an input pixel as a pixel of said background if a difference between said input pixel and a background reference pixel is less than a threshold difference comprises the steps of: (a) determining a difference between a chromatic value for said input pixel and a chromatic value for said background reference pixel; and (b) comparing said difference to a threshold chromatic value.
Claim 30
Dependent Claim
33 words
The method of claim 26 wherein at least one of said chromatic values of said input pixel, said background reference pixel and said threshold comprises a sum of a plurality of chromatic components.
Claim 31
Dependent Claim
24 words
The method of claim 26 wherein said threshold is a function of a standard deviation of a chromatic value of said background reference pixel.
Claim 32
Dependent Claim
31 words
The method of claim 26 wherein said chromatic value of said background reference pixel comprises a mean of a chromatic value of a plurality of background pixels from a plurality images.
Claim 33
Dependent Claim
66 words
The method of claim 25 wherein the step of revising said classification of said input pixel according to a first probability relationship if said input pixel is a pixel of said pixel structure comprises the step of assigning to said input pixel a probability that one of a plurality of neighboring pixels is a background pixel if said input pixel is a pixel of said structure.
Claim 34
Dependent Claim
66 words
The method of claim 25 wherein the step of revising said classification of said input pixel according to a second probability relationship if said input pixel is a pixel of said pixel structure comprises the step of assigning to said input pixel a probability that one of a plurality of neighboring pixels is a background pixel if said input pixel is a pixel of said structure.
Claim 35
Dependent Claim
57 words
The method of claim 25 wherein the step of revising a background reference pixel if said revised classification of a spatially corresponding input pixel classifies said input pixel as a background pixel comprises the step of calculating the mean of a chromatic value of said background reference pixel and said spatially corresponding input pixel of said background.
References Cited (Backward Citations)
US4448200A
Cited
US4521106A
Cited
US4697176A
Cited
US5202762A
Cited
US5249039A
Cited
USRE38420E1
Cited
US5398075A
Cited
US5684898A
Cited
US5400081A
Cited
US5748775A
Cited
US5592236A
Cited
US5812787A
Cited
US6522787B1
Cited
US5915044A
Cited
US5923380A
Cited
US5574511A
Cited
US5781198A
Cited
US6134345A
Cited
US6570608B1
Cited
US6798897B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2008-06-27 | 2008-12-27 | 2009-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2012-06-27 | 2012-12-27 | 2013-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2016-06-27 | 2016-12-27 | 2017-06-28 | $7700.00 | Window Closed / Lapsed |