US5901254A
Expired / Lapsed
US
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Apparatus and method for image reduction
Assignee: Hitachi Ltd
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Filing: 1997-08-12
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Granted: 1999-05-04
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Expires: 2017-08-12
Abstract
Abstract The present invention provides an image reducing system and method capable of retaining fine lines in a reduced image by reducing an original image and by quickly forming the reduced image with high quality. The method includes specifying positions of pixels of a reduced image in the original image according to reduction ratios, extracting a run of pieces of the same color information about the color of the pixels of the original image as a line, determining the line width of the extracted line and determining the line width after reduction in the reduction ratios based on the line width of the extracted line and calculating the centroid of the extracted line, and retaining the color information about the extracted line at a reduced pixel near the centroid on the basis of the centroid of the extracted line and the line width after reduction. The method further performs the step of determining the color information about each reduced pixel based on the retained color information.
Inventors
- 👤 Hiroaki Iguchi
- 👤 Yasuo Kurosu
- 👤 Yoshihiro Yokoyama
- 👤 Hiroshi Abei
- 👤 Masaaki Fujinawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:28
CPC Classifications
G; G06; G06T; G06T3/00; G06T3/40; G06T3/4023
Claims Analysis
Total Claims: 43
Claim 1
Independent Claim
224 words
An image reducing system comprising: an image input unit for entering an original image; an image reducing unit that reduces the original image entered by the image input unit based on reduction ratios; and an output unit that provides a reduced image formed by the image reducing unit; wherein said image reducing unit includes: a reduced pixel position specifying unit which specifies positions for reduced pixels relative to the original image based on the reduction ratios; a reference pixel block determining unit which determines a plurality of reference pixel blocks in the original image, each of said plurality of reference pixel blocks containing original image pixels and being defined by points corresponding to four reduced pixel positions specified by the reduced pixel position specifying unit; a line extracting unit which extracts color information representing colors of original image pixels in each of said plurality of reference pixel blocks determined by the reference pixel block determining unit, said colors including at least one foreground color and at least one background color; and a pixel color determining unit which determines color information about at least one reduced pixel based on color information from said line extracting unit representing colors of original image pixels in a predetermined number of reference pixel blocks surrounding a position of said at least one reduced pixel relative to the original image.
Claim 2
Dependent Claim
224 words
An image reducing system comprising: an image input unit for entering an original image; an image reducing unit that reduces the original image entered by the image input unit based on reduction ratios; and an output unit that provides a reduced image formed by the image reducing unit; wherein said image reducing unit includes: a reduced pixel position specifying unit which specifies positions for reduced pixels relative to the original image based on the reduction ratios; a reference pixel block determining unit which determines a plurality of reference pixel blocks in the original image, each of said plurality of reference pixel blocks containing original image pixels and being defined by points corresponding to four reduced pixel positions specified by the reduced pixel position specifying unit; a line extracting unit which extracts color information representing colors of original image pixels in each of said plurality of reference pixel blocks determined by the reference pixel block determining unit, said colors including at least one foreground color and at least one background color; and a pixel color determining unit which determines color information about at least one reduced pixel based on color information from said line extracting unit representing colors of original image pixels in a predetermined number of reference pixel blocks surrounding a position of said at least one reduced pixel relative to the original image.
Claim 3
Dependent Claim
69 words
An image reducing system according to claim 1, wherein the reduced pixel position specifying unit determines reduced pixel positions at horizontal intervals of 1/n x and at vertical intervals of 1/n y , where n x is a horizontal conversion ratio smaller than 1 (one), n y is a vertical conversion ratio smaller than 1 (one), and the intervals of the pixels of the original image is 1 (one).
Claim 4
Dependent Claim
16 words
An image reducing system according to claim 1, wherein said output unit is a display device.
Claim 5
Dependent Claim
78 words
An image reducing system according to claim 3, wherein the line extracting unit identifies adjacent pixels in the original image which are of a same color as at least one line in the original image, and wherein said pixel color determining unit generates a line of color in the reduced image corresponding to said at least one line in the original image if said at least one line in the original image is longer than a predetermined length.
Claim 6
Dependent Claim
75 words
An image reducing system according to claim 1, wherein the pixel color determining unit determines color information about said at least one reduced pixel by performing a logical OR of color values generated for said at least one reduced pixel, said color values being generated based on the color information in respective ones of said predetermined number of reference pixel blocks surrounding the position of said at least one reduced pixel in the original image.
Claim 7
Dependent Claim
66 words
An image reducing system according to claim 1, wherein the image reducing unit holds beforehand a pattern of color information for each reduced pixel corresponding to pixels in the original image, in a reference pixel block corresponding to the reduction ratios, and achieves image reduction by matching the pattern and the pixels in the original image in the reference pixel block corresponding to the reduction ratios.
Claim 8
Dependent Claim
16 words
An image reducing system according to claim 1, wherein said output unit is a printer device.
Claim 9
Dependent Claim
16 words
An image reducing system according to claim 1, wherein said output unit is a facsimile device.
Claim 10
Dependent Claim
16 words
An image reducing system according to claim 4, wherein said output unit is a display device.
Claim 11
Dependent Claim
16 words
An image reducing system according to claim 4, wherein said output unit is a printer device.
Claim 12
Dependent Claim
16 words
An image reducing system according to claim 4, wherein said output unit is a facsimile device.
Claim 13
Independent Claim
122 words
A method of reducing an original image, comprising the steps of: specifying positions of pixels of a reduced image relative to the original image according to reduction ratios; determining a plurality of reference pixel blocks in the original image, each of said plurality of reference pixel blocks containing original image pixels and being defined by four specified positions of reduced pixels; extracting color information representing colors of original image pixels in each of said plurality of reference pixel blocks; and determining color information about at least one reduced pixel based on color information representing colors of original image pixels in a predetermined number of reference pixel blocks surrounding a position of said at least one reduced pixel relative to the original image.
Claim 14
Independent Claim
122 words
A method of reducing an original image, comprising the steps of: specifying positions of pixels of a reduced image relative to the original image according to reduction ratios; determining a plurality of reference pixel blocks in the original image, each of said plurality of reference pixel blocks containing original image pixels and being defined by four specified positions of reduced pixels; extracting color information representing colors of original image pixels in each of said plurality of reference pixel blocks; and determining color information about at least one reduced pixel based on color information representing colors of original image pixels in a predetermined number of reference pixel blocks surrounding a position of said at least one reduced pixel relative to the original image.
Claim 15
Dependent Claim
72 words
A method according to claim 12, further comprising the steps of: identifying adjacent pixels in the original image which are of a same color as at least one line in the original image; and generating a line of color in said reduced image corresponding to said at least one line of color in the original image if said at least one line of color in the original image exceeds a predetermined length.
Claim 16
Independent Claim
140 words
A method for reducing an image, comprising: specifying at least one reduction ratio for an original image; and converting the original image into a reduced image in accordance with steps which include: dividing the original image into a plurality of pixel blocks based on said at least one reduction ratio, each of said plurality of pixel blocks containing original image pixels; calculating, based on said at least one reduction ratio, position information for pixels in the reduced image relative to the original image; determining a color of at least one pixel in the reduced image based on color information of pixels in a predetermined number of pixel blocks surrounding a position of said at least one pixel in the reduced image relative to the original image; and generating the reduced image based on said position information and said color information.
Claim 17
Independent Claim
140 words
A method for reducing an image, comprising: specifying at least one reduction ratio for an original image; and converting the original image into a reduced image in accordance with steps which include: dividing the original image into a plurality of pixel blocks based on said at least one reduction ratio, each of said plurality of pixel blocks containing original image pixels; calculating, based on said at least one reduction ratio, position information for pixels in the reduced image relative to the original image; determining a color of at least one pixel in the reduced image based on color information of pixels in a predetermined number of pixel blocks surrounding a position of said at least one pixel in the reduced image relative to the original image; and generating the reduced image based on said position information and said color information.
Claim 18
Dependent Claim
88 words
A method according to claim 14, wherein said determining step includes: assigning a plurality of color values to said at least one pixel in the reduced image, said plurality of color values determined based on colors of original image pixels in respective ones of said predetermined number of pixel blocks, and determining the color of said at least one pixel in the reduced image based on a logical OR operation performed on said plurality of color values assigned to said at least one pixel in the reduced image.
Claim 19
Dependent Claim
60 words
A method according to claim 15, wherein said plurality of color values assigned to said at least one pixel in the reduced image are determined by referencing a conversion table stored in memory, which conversion table matches said plurality of color values with patterns of colors of original image pixels in respective ones of said predetermined number of pixel blocks.
Claim 20
Dependent Claim
14 words
A method according to claim 14, wherein said predetermined number of pixel is four.
Claim 21
Dependent Claim
23 words
A method according to claim 14, wherein said at least one reduction ratio includes a horizontal reduction ratio and a vertical reduction ratio.
Claim 22
Dependent Claim
24 words
A method according to claim 14, wherein said plurality of pixel blocks are of a size proportional to said at least one reduction ratio.
Claim 23
Dependent Claim
29 words
A method according to claim 19, wherein said at least one reduction ratio is selected so that said plurality of pixel blocks have differing numbers of rows and columns.
Claim 24
Dependent Claim
29 words
A method according to claim 14, wherein said plurality of pixel blocks are of different sizes determined by specifying different reduction ratios for selected portions of said original image.
Claim 25
Dependent Claim
48 words
A method according to claim 14, further comprising: identifying lines of a color in said plurality of pixel blocks of original image pixels; and generating lines of color in said reduced image corresponding to said lines of color in said plurality of pixel blocks of original image pixels.
Claim 26
Dependent Claim
75 words
A method according to claim 22, further comprising: comparing a length of each of said lines of color identified in said plurality of pixel blocks of original image pixels with a predetermined length; and producing in said reduced image only those lines of color, corresponding to said lines of color in said plurality of pixel blocks of original image pixels, having lengths longer than said predetermined length, to thereby reduce noise in the reduced image.
Claim 27
Dependent Claim
67 words
A method according to claim 22, further comprising: comparing a width of each of said lines of color identified in said plurality of pixel blocks of original image pixels with a predetermined width; and producing in said reduced image only those lines of color, corresponding to said lines of color in said plurality of pixel blocks of original image pixels, having widths greater than said predetermined width.
Claim 28
Dependent Claim
17 words
A method according to claim 14, wherein said original image and said reduced image are halftone images.
Claim 29
Dependent Claim
30 words
A method according to claim 14, wherein said original image and said reduced image are images containing at least one color in addition to the colors of black and white.
Claim 30
Independent Claim
147 words
A system for reducing an image, comprising: an input unit for receiving at least one reduction ratio for an original image; an image extracting unit for dividing the original image into a plurality of pixel blocks based on said at least one reduction ratio, each of said plurality of pixel blocks containing original image pixels; a calculating unit for calculating position information for pixels in the reduced image relative to the original image based on said at least one reduction ratio; a color determining unit for determining a color of at least one pixel in the reduced image based on color information of pixels in a predetermined number of pixel blocks surrounding a position of said at least one pixel in the reduced image relative to the original image; and a generating unit for generating the reduced image based on said position information and said color information.
Claim 31
Independent Claim
147 words
A system for reducing an image, comprising: an input unit for receiving at least one reduction ratio for an original image; an image extracting unit for dividing the original image into a plurality of pixel blocks based on said at least one reduction ratio, each of said plurality of pixel blocks containing original image pixels; a calculating unit for calculating position information for pixels in the reduced image relative to the original image based on said at least one reduction ratio; a color determining unit for determining a color of at least one pixel in the reduced image based on color information of pixels in a predetermined number of pixel blocks surrounding a position of said at least one pixel in the reduced image relative to the original image; and a generating unit for generating the reduced image based on said position information and said color information.
Claim 32
Dependent Claim
92 words
A system according to claim 27, wherein said color determining unit assigns a plurality of color values to said at least one pixel in the reduced image, said plurality of colors determined based on colors of original image pixels in respective ones of said predetermined number of pixel blocks, and wherein said color determining unit determines the color of said at least one pixel in the reduced image based on a logical OR operation performed on said plurality of color values assigned to said at least one pixel in the reduced image.
Claim 33
Dependent Claim
63 words
A system according to claim 28, wherein said color determining unit determines said plurality of color values assigned to said at least one pixel in the reduced image by referencing a conversion table stored in memory, which conversion table matches said plurality of color values with patterns of colors of original image pixels in respective ones of said predetermined number of pixel blocks.
Claim 34
Dependent Claim
15 words
A system according to claim 27, wherein said predetermined number of pixel blocks is four.
Claim 35
Dependent Claim
23 words
A system according to claim 27, wherein said at least one reduction ratio includes a horizontal reduction ratio and a vertical reduction ratio.
Claim 36
Dependent Claim
24 words
A system according to claim 27, wherein said plurality of pixel blocks are of a size proportional to said at least one reduction ratio.
Claim 37
Dependent Claim
29 words
A system according to claim 27, wherein said at least one reduction ratio is selected so that said plurality of pixel blocks have differing numbers of rows and columns.
Claim 38
Dependent Claim
29 words
A system according to claim 27, wherein said plurality of pixel blocks are of different sizes determined by specifying different reduction ratios for selected portions of said original image.
Claim 39
Dependent Claim
58 words
A system according to claim 27, further comprising: a line identifying unit for identifying lines of a color in said plurality of pixel blocks of original image pixels; and a line generating unit for generating lines of color in said reduced image corresponding to said lines of color in said plurality of pixel blocks of original image pixels.
Claim 40
Dependent Claim
81 words
A system according to claim 35, further comprising: a unit for comparing a length of each of said lines of color identified in said plurality of pixel blocks of original image pixels with a predetermined length; and a unit for generating in said reduced image only those lines of color, corresponding to said lines of color in said plurality of pixel blocks of original image pixels, having lengths longer than said predetermined length, to thereby reduce noise in the reduced image.
Claim 41
Dependent Claim
72 words
A system according to claim 35, further comprising: a unit for comparing a width of each of said lines of color identified in said plurality of pixel blocks of original image pixels with a predetermined width; and means for generating in said reduced image only those lines of color, corresponding to said lines of color in said plurality of pixel blocks of original image pixels, having widths greater than said predetermined width.
Claim 42
Dependent Claim
17 words
A system according to claim 27, wherein said original image and said reduced image are halftone images.
Claim 43
Dependent Claim
30 words
A system according to claim 27, wherein said original image and said reduced image are images containing at least one color in addition to the colors of black and white.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-05-03 | 2002-11-02 | 2003-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-05-03 | 2006-11-02 | 2007-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-05-03 | 2010-11-02 | 2011-05-04 | $7700.00 | Window Closed / Lapsed |