Patent US5299308A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5299308A Expired / Lapsed US ⏱️ 0.0 years remaining

Graphic data processing apparatus for producing a tone for an edge pixel and reducing aliasing effects

Assignee: Ricoh Co Ltd
•
Filing: 1991-02-22
•
Granted: 1994-03-29
•
Expires: 2011-02-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The tones (or densities) of individual edge pixels of vector data are determined by first dividing each edge pixel into subpixels, after which the thus-determined tones are fed to a laser printer or other output unit. Advantageously, the present invention smooths jagged edges by performing an anti-aliasing process. To achieve this smoothing of graphic data, any of a variety of filters, each having particular weights, are used for the process of dividing edge pixels into subpixels.

Inventors

  • 👤 Hiroaki Suzuki
  • 👤 Naofumi Ueda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 17:51
CPC Classifications
G; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K15/1204; G06K15/1209; G06K15/1223; G06K15/128

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 99 words
A graphic data processing apparatus for producing a tone of an edge pixel of vector data in a manner to reduce aliasing effects, the apparatus comprising: a) dividing means for dividing an edge pixel of vector data into subpixels by using a way of dividing; b) varying means for varying the way of dividing the edge pixel, in matching relation to an inclination of the vector data; and c) determining means, including: 1) means for calculating an area ratio by using the subpixels; and 2) means for determining the tone of the edge pixel based on the area ratio.
Claim 2
Dependent Claim 99 words
A graphic data processing apparatus for producing a tone of an edge pixel of vector data in a manner to reduce aliasing effects, the apparatus comprising: a) dividing means for dividing an edge pixel of vector data into subpixels by using a way of dividing; b) varying means for varying the way of dividing the edge pixel, in matching relation to an inclination of the vector data; and c) determining means, including: 1) means for calculating an area ratio by using the subpixels; and 2) means for determining the tone of the edge pixel based on the area ratio.
Claim 3
Dependent Claim 12 words
An apparatus as claimed in claim 1, wherein the tone comprises density.
Claim 4
Dependent Claim 16 words
An apparatus as claimed in claim 1, wherein the tone is fed to an output unit.
Claim 5
Dependent Claim 16 words
An apparatus as claimed in claim 3, wherein said output unit comprises a multi-level output unit.
Claim 6
Dependent Claim 15 words
An apparatus as claimed in claim 3, wherein said output unit comprises a laser printer.
Claim 7
Dependent Claim 37 words
An apparatus as claimed in claim 1, wherein: said varying means includes means for varying a configuration in which said dividing means divides the edge pixel on the basis of feature data particular to the vector data.
Claim 8
Dependent Claim 18 words
The apparatus of claim 1, wherein the varying means includes: means for varying a size of the subpixels.
Claim 9
Dependent Claim 18 words
The apparatus of claim 1, wherein the varying means includes: means for varying a shape of the subpixels.
Claim 10
Dependent Claim 18 words
The apparatus of claim 1, wherein the varying means includes: means for varying an orientation of the subpixels.
Claim 11
Dependent Claim 85 words
A graphic data processing apparatus for determining a tone of an edge pixel of vector data, the apparatus comprising: means for selecting, among a plurality of subpixel configurations, a particular subpixel configuration on the basis of whether or not a marginal point exists in said edge pixel; means for dividing the edge pixel into subpixels in the particular subpixel configuration selected by said selecting means; and means for outputting the tone based on a division of the edge pixel based on the particular subpixel configuration.
Claim 12
Dependent Claim 85 words
A graphic data processing apparatus for determining a tone of an edge pixel of vector data, the apparatus comprising: means for selecting, among a plurality of subpixel configurations, a particular subpixel configuration on the basis of whether or not a marginal point exists in said edge pixel; means for dividing the edge pixel into subpixels in the particular subpixel configuration selected by said selecting means; and means for outputting the tone based on a division of the edge pixel based on the particular subpixel configuration.
Claim 13
Dependent Claim 54 words
An apparatus as claimed in claim 10, wherein said plurality of pixel configurations include: a quadrilateral formed by dividing an edge pixel into 1 * N subpixels, a quadrilateral formed by dividing an edge pixel into N * 1 subpixels, and a quadrilateral formed by dividing an edge pixel into N * M subpixels.
Claim 14
Dependent Claim 90 words
A graphic data processing apparatus for producing a tone of an edge pixel of vector data, comprising: a) dividing means for dividing an edge pixel into subpixels; and b) tone determining means including: 1) means for dividing said edge pixel into (i) a division region which is to be divided into subpixels and (ii) a non-division region which is not to be divided into subpixels; and 2) means for determining the tone on the basis of the number of subpixels of said division region which are covered by an image.
Claim 15
Dependent Claim 90 words
A graphic data processing apparatus for producing a tone of an edge pixel of vector data, comprising: a) dividing means for dividing an edge pixel into subpixels; and b) tone determining means including: 1) means for dividing said edge pixel into (i) a division region which is to be divided into subpixels and (ii) a non-division region which is not to be divided into subpixels; and 2) means for determining the tone on the basis of the number of subpixels of said division region which are covered by an image.
Claim 16
Dependent Claim 159 words
A graphic data processing apparatus for producing a tone of an edge pixel of vector data, comprising: a) dividing means for dividing an edge pixel of vector data into subpixels; b) deciding means for determining a decision result, on the basis of (1) an inclination of vector data traversing an edge pixel and (2) the kind of an edge, the decision result constituting a decision as to which of upper, lower, left and right portions of said edge pixel an image to be painted is positioned; c) storing means for storing a first, a second, a third and a fourth weighing filter to be used when said image to be painted is positioned in said upper portion, said lower portion, said right portion, and said left portion of said edge pixel, respectively; and d) tone determining means for determining the tone of said edge pixel by selecting, one of said first to fourth weighting filters matching said decision result.
Claim 17
Dependent Claim 159 words
A graphic data processing apparatus for producing a tone of an edge pixel of vector data, comprising: a) dividing means for dividing an edge pixel of vector data into subpixels; b) deciding means for determining a decision result, on the basis of (1) an inclination of vector data traversing an edge pixel and (2) the kind of an edge, the decision result constituting a decision as to which of upper, lower, left and right portions of said edge pixel an image to be painted is positioned; c) storing means for storing a first, a second, a third and a fourth weighing filter to be used when said image to be painted is positioned in said upper portion, said lower portion, said right portion, and said left portion of said edge pixel, respectively; and d) tone determining means for determining the tone of said edge pixel by selecting, one of said first to fourth weighting filters matching said decision result.

References Cited (Backward Citations)

US4607340A Cited
US4827352A Cited
US4965672A Cited
US4840460A Cited
US5086484A Cited
US4908780A Cited
GB2223916A Cited
US5012257A Cited
US5140315A Cited
US5029108A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-03-28 1997-09-27 1998-03-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-03-28 2001-09-27 2002-03-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-03-28 2005-09-27 2006-03-29 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag