US6934412B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detecting small amounts of color in an image
Assignee: Xerox Corp
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Filing: 2000-12-15
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Granted: 2005-08-23
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Expires: 2020-12-15
Abstract
Abstract A method for classifying an image as one of color and neutral assigns respective values associated with a plurality of pixels in the image to a plurality of respective current pixels. Reduced image pixels are produced as a function of the current pixels. The image is classified as one of neutral and color as a function of the reduced image pixels.
Inventors
- 👤 Jan Bares
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:58
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/56
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
189 words
A method for classifying an image as one of color and neutral, the method comprising: scanning an image to produce components of a first color space, representing transformed pixels of the scanned image; transforming components of the first color space into components of a three axes second color space; a) assigning respective values associated with the components of the second color space to a plurality of respective current pixels, wherein the current pixels values include color components; comparing the color component values to an upper and lower threshold value to determine if the color component values represent low-chroma components; replacing low-chroma components with neutral values; b) producing reduced image pixels as a function of the current pixels with said replaced low-chroma components; determining respective distances of each of the average pixel values from a neutral axis of the second three axis color space; determining a count of the distances exceeding a threshold, the threshold determined as a function of a position along the neutral axis; and c) classifying the image as one of neutral and color as a function of the said count of the distances exceeding a threshold.
Claim 2
Independent Claim
189 words
A method for classifying an image as one of color and neutral, the method comprising: scanning an image to produce components of a first color space, representing transformed pixels of the scanned image; transforming components of the first color space into components of a three axes second color space; a) assigning respective values associated with the components of the second color space to a plurality of respective current pixels, wherein the current pixels values include color components; comparing the color component values to an upper and lower threshold value to determine if the color component values represent low-chroma components; replacing low-chroma components with neutral values; b) producing reduced image pixels as a function of the current pixels with said replaced low-chroma components; determining respective distances of each of the average pixel values from a neutral axis of the second three axis color space; determining a count of the distances exceeding a threshold, the threshold determined as a function of a position along the neutral axis; and c) classifying the image as one of neutral and color as a function of the said count of the distances exceeding a threshold.
Claim 3
Dependent Claim
54 words
The method for classifying an image as one of color and neutral as set forth in claim 1 , wherein the producing step b) further includes: f) selecting a reduction filter; and g) averaging the current pixels with said replaced low-chroma components in accordance with the reduction filter to produce the reduced image pixels.
Claim 4
Dependent Claim
53 words
The method for classifying an image as one of color and neutral as set forth in claim 2 , wherein the averaging step g) includes: h) assigning the reduced image pixels produced by the reduction filter a value representing an average of all the reduced image pixel values included in the current filter.
Claim 5
Dependent Claim
96 words
The method for classifying an image as one of color and neutral as set forth in claim 2 , wherein before the steps of determining a count and classifying the image as a function of the count: j) assigning the respective values associated with the reduced image pixels to the plurality of respective current pixels, wherein the current pixels values include color components; comparing the color component values to an upper and lower threshold value to determine if the color component values represent low-chroma components; replacing low-chroma components with neutral values; and k) repeating step g).
Claim 6
Dependent Claim
36 words
The method for classifying an image as one of color and neutral as set forth in claim 4 , wherein the repeating step k) includes: l) repeating the step f) to select a different current filter.
Claim 7
Independent Claim
258 words
A method for rendering an image in accordance with one of a color image rendering process and a non-color image rendering process, the method comprising: a) inputting pixel values, which are representative of the image, into a memory device; transforming the pixel values into color components of a first three axes color space; for each of a plurality of color component values defining each of the pixel values: b) comparing the color component value to an upper and lower threshold value to determine if the color component value represents a low-chroma pixel; c) if the color component value does not represent a low-chroma pixel, storing the color component value into a respective color component of a current pixel; and d) if the color component value does represent a low-chroma pixel, storing a neutral value into the respective color component of the current pixel; e) determining respective average pixel values for a plurality of sub-groups of the current pixels, each of the sub-groups including a predetermined number of the pixel values; determining respective distances of each of the average pixel values from a neutral axis of a second three axis color space: determining a number of the distances exceeding a threshold, which is determined as a function of a position along the neutral axis; f) determining to render the image using one of the color image rendering process and the non-color image rendering process as a function of the said number of the distances exceeding a threshold; and g) rendering the image in accordance with the determined rendering process.
Claim 8
Independent Claim
258 words
A method for rendering an image in accordance with one of a color image rendering process and a non-color image rendering process, the method comprising: a) inputting pixel values, which are representative of the image, into a memory device; transforming the pixel values into color components of a first three axes color space; for each of a plurality of color component values defining each of the pixel values: b) comparing the color component value to an upper and lower threshold value to determine if the color component value represents a low-chroma pixel; c) if the color component value does not represent a low-chroma pixel, storing the color component value into a respective color component of a current pixel; and d) if the color component value does represent a low-chroma pixel, storing a neutral value into the respective color component of the current pixel; e) determining respective average pixel values for a plurality of sub-groups of the current pixels, each of the sub-groups including a predetermined number of the pixel values; determining respective distances of each of the average pixel values from a neutral axis of a second three axis color space: determining a number of the distances exceeding a threshold, which is determined as a function of a position along the neutral axis; f) determining to render the image using one of the color image rendering process and the non-color image rendering process as a function of the said number of the distances exceeding a threshold; and g) rendering the image in accordance with the determined rendering process.
Claim 9
Dependent Claim
46 words
The method for rendering an image as set forth in claim 6 , wherein the step f) of determining includes: h) determining a count of the respective average pixels having at least one of a plurality of corresponding color components within a range of color values.
Claim 10
Dependent Claim
63 words
The method for rendering an image as set forth in claim 6 , wherein the step g) of rendering includes: h) if the image is rendered in accordance with the non-color image rendering process, rendering the image using one colorant; and i) if the image is rendered in accordance with the color image rendering process, rendering the image using a plurality of colorants.
Claim 11
Dependent Claim
31 words
The method for rendering an image as set forth in claim 8 , wherein the step g) of rendering further includes: j) rendering the image on a digital color output device.
Claim 12
Dependent Claim
37 words
The method for rendering an image as set forth in claim 6 , further including, before the steps f) and g) of determining and rendering: h) repeating the steps b) through e) for the average pixel values.
Claim 13
Dependent Claim
36 words
The method for rendering an image as set forth in claim 10 , wherein the step h) of repeating includes: i) repeating the step e) using sub-groups including a different predetermined number of the current pixels.
Claim 14
Independent Claim
141 words
A system for classifying an image as one of color and neutral, comprising: means for assigning respective values associated with a plurality of pixels in the image to a plurality of respective current pixels; means for determining, as a function of the current pixel values and a plurality of neutral thresholds, if any of the current pixels include a low-chroma component; means for producing reduced image pixels as a function of the current pixels; determining respective distances of each of the reduced image pixels from a neutral axis of a three axis color space; determining a count of the distances exceeding a threshold, which is determined as a function of a position along the neutral axis; and means for classifying the image as one of neutral and color as a function of the said count of the distances exceeding a threshold.
Claim 15
Independent Claim
141 words
A system for classifying an image as one of color and neutral, comprising: means for assigning respective values associated with a plurality of pixels in the image to a plurality of respective current pixels; means for determining, as a function of the current pixel values and a plurality of neutral thresholds, if any of the current pixels include a low-chroma component; means for producing reduced image pixels as a function of the current pixels; determining respective distances of each of the reduced image pixels from a neutral axis of a three axis color space; determining a count of the distances exceeding a threshold, which is determined as a function of a position along the neutral axis; and means for classifying the image as one of neutral and color as a function of the said count of the distances exceeding a threshold.
Claim 16
Dependent Claim
88 words
The system for classifying an image as set forth in claim 12 , wherein the means for producing includes: means for generating intermediate pixels in accordance with: if a current one of the current pixels is determined not to include a low-chroma component, a value of the corresponding intermediate pixel being generated as the value of the current pixel; and if a current one of the current pixels is determined to include a low-chroma component, a value of the corresponding intermediate pixel being generated as a neutral value.
Claim 17
Dependent Claim
39 words
The system for classifying an image as set forth in claim 13 , wherein the means for producing selects a current filter and averages the intermediate pixels in accordance with the current filter to produce the reduced image pixels.
Claim 18
Dependent Claim
48 words
The system for classifying an image as set forth in claim 14 , wherein the means for classifying determines a count of the reduced image pixels having values above a color threshold, the image being classified as one of color and neutral as a function of the count.
Claim 19
Dependent Claim
31 words
The system for classifying an image as set forth in claim 15 , wherein the classifying means determines a fraction of the reduced image pixels including a predetermined level of color.
Claim 20
Dependent Claim
45 words
The system for classifying an image as set forth in claim 16 , wherein the means for producing recursively produces reduced image pixels as a function of previously produced reduced image pixels, the image being classified as a function of the final reduced image pixel.
References Cited (Backward Citations)
US5233413A
Cited
US5282026A
Cited
US5883968A
Cited
US6510246B1
Cited
US6240203B1
Cited
US6160644A
Cited
US6249592B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2008-08-22 | 2009-02-21 | 2009-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2012-08-22 | 2013-02-21 | 2013-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2016-08-22 | 2017-02-21 | 2017-08-23 | $7700.00 | Window Closed / Lapsed |