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US6044178A Expired / Lapsed US ⏱️ 0.0 years remaining

LCD projector resolution translation

Assignee: Seiko Epson Corp
•
Filing: 1998-03-10
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Granted: 2000-03-28
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Expires: 2018-03-10
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Abstract

Abstract A source image containing both relatively low frequency information (i.e. graphics, pictures and background) and relatively high frequency information (i.e. text) are input to an image processing unit. This image processing unit can be embodied in functional units of an output device such as an LCD projector or may be part of a personal computer connected to the output device, or may even be part of an input device that provides the source image. The source image will be in one resolution and the output device will have a different, generally lower, resolution. The source image is segmented into a black text image and a white text image (i.e. portions of the source image formed as image blocks or tiles). The black text image and the white text image are then subtracted from the source image to form a background image. Then, the background image, the black text image and the white text image are filtered separately using different filters for each. The filtered or down-sampled images are then merged. This merged image can then be projection enlarged, in the example wherein the output device is an LCD projector, or printed or displayed in the examples wherein the output device is a printer or CRT, respectively. The filter for the background image is preferably a gaussian filter and the filters for the black text image and the white text images are preferably a combination of a gaussian filter (having different filter coefficients than the filter for the background image) and a sigmoid filter.

Inventors

  • 👤 Shang-Hung Lin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 14:22
CPC Classifications
G; G06; G06T; G06T3/00; G06T3/40

Claims Analysis

Total Claims: 47
Claim 1
Independent Claim 238 words
An image processing apparatus for translating a source image in a first resolution from an input device into an output image in a second resolution for an output device comprising: an image buffer for receiving and storing said source image; a text segmentation unit for forming a black text image and a white text image from said source image stored in said image buffer; a black text image buffer for storing said black text image and a white text image buffer for storing said white text image; an image separation unit coupled to said image buffer, said black text image buffer and said white text image buffer for separating said black text image and said white text image from said source image to form a background image; a first filter for filtering said black text image to produce a filtered black text image and a first resultant buffer for storing said filtered black text image; a second filter for filtering said white text image to produce a filtered white text image and a second resultant buffer for storing said filtered white text image; a third filter for filtering said background image to produce a filtered background image and a third resultant buffer for storing said filtered background image; an image merging unit coupled to said first, second and third resultant buffers for combining said filtered black, white, and background images into an output image in said second resolution.
Claim 2
Dependent Claim 238 words
An image processing apparatus for translating a source image in a first resolution from an input device into an output image in a second resolution for an output device comprising: an image buffer for receiving and storing said source image; a text segmentation unit for forming a black text image and a white text image from said source image stored in said image buffer; a black text image buffer for storing said black text image and a white text image buffer for storing said white text image; an image separation unit coupled to said image buffer, said black text image buffer and said white text image buffer for separating said black text image and said white text image from said source image to form a background image; a first filter for filtering said black text image to produce a filtered black text image and a first resultant buffer for storing said filtered black text image; a second filter for filtering said white text image to produce a filtered white text image and a second resultant buffer for storing said filtered white text image; a third filter for filtering said background image to produce a filtered background image and a third resultant buffer for storing said filtered background image; an image merging unit coupled to said first, second and third resultant buffers for combining said filtered black, white, and background images into an output image in said second resolution.
Claim 3
Dependent Claim 21 words
An apparatus according to claim 1 wherein said first filter is a combination of a gaussian filter and a sigmoid filter.
Claim 4
Dependent Claim 21 words
An apparatus according to claim 2 wherein said second filter is a combination of a gaussian filter and a sigmoid filter.
Claim 5
Dependent Claim 13 words
An apparatus according to claim 3 wherein said third filter is gaussian filter.
Claim 6
Dependent Claim 29 words
An apparatus according to claim 1 further comprising a thresholding unit coupled to said image buffer for labeling pixels in said source image according to each pixels intensity value.
Claim 7
Dependent Claim 25 words
An apparatus according to claim 5 further comprising a text mask coupled to said thresholding unit for filtering out non-text images from said source image.
Claim 8
Dependent Claim 21 words
An apparatus according to claim 6 further comprising a binary frame buffer coupled to said text mask for storing text images.
Claim 9
Dependent Claim 28 words
An apparatus according to claim 5 further comprising a line buffer coupled between said thresholding unit and said text segmentation unit for storing a line of threshold-labeled pixels.
Claim 10
Dependent Claim 14 words
An apparatus according to claim 1 wherein said output device is an LCD projector.
Claim 11
Dependent Claim 23 words
An apparatus according to claim 9 wherein said LCD projector comprises an LCD panel for displaying said output image in said second resolution.
Claim 12
Dependent Claim 23 words
An apparatus according to claim 10 wherein said input device is a personal computer for providing said source image in a first resolution.
Claim 13
Independent Claim 115 words
A method for translating a source image in a first resolution from an input device into an output image in a second resolution for an output device comprising: receiving said source image; segmenting said source image into a black text image and a white text image; separating said black text image and said white text image from said source image to form a background image; filtering said black text image to produce a filtered black text image; filtering said white text image to produce a filtered white text image; filtering said background image to produce a filtered background image; merging said filtered black, white, and background images into an output image in said second resolution.
Claim 14
Independent Claim 115 words
A method for translating a source image in a first resolution from an input device into an output image in a second resolution for an output device comprising: receiving said source image; segmenting said source image into a black text image and a white text image; separating said black text image and said white text image from said source image to form a background image; filtering said black text image to produce a filtered black text image; filtering said white text image to produce a filtered white text image; filtering said background image to produce a filtered background image; merging said filtered black, white, and background images into an output image in said second resolution.
Claim 15
Dependent Claim 32 words
A method according to claim 12 wherein said step of filtering said black text image includes first passing said black text image through a gaussian filter and then through a sigmoid filter.
Claim 16
Dependent Claim 34 words
A method according to claim 13 wherein said step of filtering said black text image includes tap-shifting pixels such that said gaussian filter is shifted toward an edge of at least one text pixel.
Claim 17
Dependent Claim 32 words
A method according to claim 13 wherein said step of filtering said white text image includes first passing said white text image through a gaussian filter and then through a sigmoid filter.
Claim 18
Dependent Claim 34 words
A method according to claim 15 wherein said step of filtering said white text image includes tap-shifting pixels such that said gaussian filter is shifted toward an edge of at least one text pixel.
Claim 19
Dependent Claim 23 words
A method according to claim 15 wherein said step of filtering said background image includes passing said background image through a gaussian filter.
Claim 20
Dependent Claim 28 words
An method according to claim 12 further comprising a thresholding step of labeling pixels in said source image according to each pixel's intensity value before said segmenting step.
Claim 21
Dependent Claim 23 words
A method according to claim 18 further comprising a step of masking out non-text images from said source image following said thresholding step.
Claim 22
Dependent Claim 23 words
A method according to claim 19 further comprising a step of storing text images in a binary frame buffer following said masking step.
Claim 23
Dependent Claim 24 words
A method according to claim 12 further comprising a step of projection displaying said output image in a second resolution on an LCD projector.
Claim 24
Dependent Claim 20 words
A method according to claim 21 wherein said projection displaying step comprises displaying said output image with an LCD panel.
Claim 25
Dependent Claim 23 words
A method according to claim 22 further comprising the step of providing said source image in a first resolution from a personal computer.
Claim 26
Independent Claim 135 words
A medium readable by a machine embodying a program of instructions executable by said machine to perform a method of translating a source image in a first resolution from an input device into an output image in a second resolution for an output device, said translating method comprising: receiving said source image; segmenting said source image into a black text image and a white text image; separating said black text image and said white text image from said source image to form a background image; filtering said black text image to produce a filtered black text image; filtering said white text image to produce a filtered white text image; filtering said background image to produce a filtered background image; merging said filtered black, white, and background images into an output image in said second resolution.
Claim 27
Independent Claim 135 words
A medium readable by a machine embodying a program of instructions executable by said machine to perform a method of translating a source image in a first resolution from an input device into an output image in a second resolution for an output device, said translating method comprising: receiving said source image; segmenting said source image into a black text image and a white text image; separating said black text image and said white text image from said source image to form a background image; filtering said black text image to produce a filtered black text image; filtering said white text image to produce a filtered white text image; filtering said background image to produce a filtered background image; merging said filtered black, white, and background images into an output image in said second resolution.
Claim 28
Dependent Claim 36 words
A medium according to claim 24 wherein in said translating method said step of filtering said black text image includes first passing said black text image through a gaussian filter and then through a sigmoid filter.
Claim 29
Dependent Claim 38 words
A medium according to claim 25 wherein in said translating method said step of filtering said black text image includes tap-shifting pixels such that said gaussian filter is shifted toward an edge of at least one text pixel.
Claim 30
Dependent Claim 36 words
A medium according to claim 25 wherein in said translating method said step of filtering said white text image includes first passing said white text image through a gaussian filter and then through a sigmoid filter.
Claim 31
Dependent Claim 38 words
A medium according to claim 27 wherein in said translating method said step of filtering said white text image includes tap-shifting pixels such that said gaussian filter is shifted toward an edge of at least one text pixel.
Claim 32
Dependent Claim 27 words
A medium according to claim 27 wherein in said translating method said step of filtering said background image includes passing said background image through a gaussian filter.
Claim 33
Dependent Claim 32 words
A medium according to claim 24 wherein said translating method further comprises a thresholding step of labeling pixels in said source image according to each pixel's intensity value before said segmenting step.
Claim 34
Dependent Claim 27 words
A medium according to claim 30 wherein said translating method further comprises a step of masking out non-text images from said source image following said thresholding step.
Claim 35
Dependent Claim 27 words
A medium according to claim 31 wherein said translating method further comprises a step of storing text images in a binary frame buffer following said masking step.
Claim 36
Dependent Claim 28 words
A medium according to claim 24 wherein said translating method further comprises a step of projection displaying said output image in a second resolution on an LCD projector.
Claim 37
Dependent Claim 24 words
A medium according to claim 33 wherein in said translating method said projection displaying step comprises displaying said output image with an LCD panel.
Claim 38
Dependent Claim 27 words
A method according to claim 34 wherein said translating method further comprising the step of providing said source image in a first resolution from a personal computer.
Claim 39
Independent Claim 268 words
A system for translating a source image in a first resolution from an input device into an output image in a second resolution for an output device comprising: an input device for providing said source image in said first resolution; an image buffer for receiving said source image from said input device and storing said source image; a text segmentation unit for forming a black text image and a white text image from said source image stored in said image buffer; a black text image buffer for storing said black text image and a white text image buffer for storing said white text image; an image separation unit coupled to said image buffer, said black text image buffer and said white text image buffer for separating said black text image and said white text image from said source image to form a background image; a first filter for filtering said black text image to produce a filtered black text image and a first resultant buffer for storing said filtered black text image; a second filter for filtering said white text image to produce a filtered white text image and a second resultant buffer for storing said filtered white text image; a third filter for filtering said background image to produce a filtered background image and a third resultant buffer for storing said filtered background image; an image merging unit coupled to said first, second and third resultant buffers for combining said filtered black, white, and background images into an output image in said second resolution; and an output device for outputting said output image in said second resolution.
Claim 40
Independent Claim 268 words
A system for translating a source image in a first resolution from an input device into an output image in a second resolution for an output device comprising: an input device for providing said source image in said first resolution; an image buffer for receiving said source image from said input device and storing said source image; a text segmentation unit for forming a black text image and a white text image from said source image stored in said image buffer; a black text image buffer for storing said black text image and a white text image buffer for storing said white text image; an image separation unit coupled to said image buffer, said black text image buffer and said white text image buffer for separating said black text image and said white text image from said source image to form a background image; a first filter for filtering said black text image to produce a filtered black text image and a first resultant buffer for storing said filtered black text image; a second filter for filtering said white text image to produce a filtered white text image and a second resultant buffer for storing said filtered white text image; a third filter for filtering said background image to produce a filtered background image and a third resultant buffer for storing said filtered background image; an image merging unit coupled to said first, second and third resultant buffers for combining said filtered black, white, and background images into an output image in said second resolution; and an output device for outputting said output image in said second resolution.
Claim 41
Dependent Claim 13 words
A system as in claim 36 wherein said input device is a scanner.
Claim 42
Dependent Claim 14 words
A system as in claim 36 wherein said input device is a personal computer.
Claim 43
Dependent Claim 14 words
A system as in claim 36 wherein said input device is a digital camera.
Claim 44
Dependent Claim 12 words
A system as in claim 36 wherein said input device is media.
Claim 45
Dependent Claim 14 words
A system as in claim 36 wherein said output device is an LCD projector.
Claim 46
Dependent Claim 13 words
A system as in claim 36 wherein said output device is a CRT.
Claim 47
Dependent Claim 13 words
A system as in claim 36 wherein said output device is a printer.

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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) 2003-03-28 2003-09-27 2004-03-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-03-28 2007-09-27 2008-03-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-03-28 2011-09-27 2012-03-28 $7700.00 Window Closed / Lapsed

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