Patent US5008752A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5008752A Expired / Lapsed US ⏱️ 0.0 years remaining

Digital image interpolator with multiple interpolation algorithms

Assignee: Eastman Kodak Co
•
Filing: 1989-06-16
•
Granted: 1991-04-16
•
Expires: 2009-06-16
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An interpolator for enlarging or reducing a digital image includes an interpolation coefficient memory containing interpolation coefficients representing several different one dimensional interpolation kernels. A row interpolator receives image pixel values, retrieves interpolation coefficients from the memory, and produces interpolated pixel values by interpolating in a row direction. A column interpolator receives multiple rows of interpolated pixel values from the row interpolator, retrieves interpolation coefficients from the memory, and produces rows of interpolated pixel values by interpolating in a column direction. A logic and control unit monitors the content of the input data and switches between interpolation kernels to provide optimum interpolation for each type of content.

Inventors

  • 👤 Lance Van Nostrand

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 21:20
CPC Classifications
G; G06; G06T; G06T3/00; G06T3/40; G06T3/4007; G06F; G06F17/00; G06F17/10; G06F17/17; G06F17/175

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 199 words
Apparatus for performing interpolation on an input digital image signal having pixel values representing rows and columns of pixels, to produce an interpolated digital image that has more (magnified) or fewer (reduced) pixels, comprising: a. an interpolation kernel lookup table containing first and second interpolation kernel coefficients; b. row interpolator means for receiving the input digital image signal, and interpolating in row direction, by retrieving interpolation coefficient values from the interpolation kernel lookup table, and applying the coefficient values to a subset of pixel values in a row to produce interpolated pixel values; c. column interpolator means for receiving rows of interpolated pixel values from the row interpolator means and preforming interpolation in a column direction by retrieving interpolation coefficient values from the interpolation lookup table, and applying the coefficient values to subsets of pixel values in a column; and d. interpolation selection means for receiving the input digital image signal input to the row interpolator means, and in response thereto, for selecting said first or second interpolation kernel for row interpolation, and for receiving the interpolated signal values from the row interpolation means, and in response thereto, for selecting said first or second interpolation kernel for column interpolation.
Claim 2
Dependent Claim 199 words
Apparatus for performing interpolation on an input digital image signal having pixel values representing rows and columns of pixels, to produce an interpolated digital image that has more (magnified) or fewer (reduced) pixels, comprising: a. an interpolation kernel lookup table containing first and second interpolation kernel coefficients; b. row interpolator means for receiving the input digital image signal, and interpolating in row direction, by retrieving interpolation coefficient values from the interpolation kernel lookup table, and applying the coefficient values to a subset of pixel values in a row to produce interpolated pixel values; c. column interpolator means for receiving rows of interpolated pixel values from the row interpolator means and preforming interpolation in a column direction by retrieving interpolation coefficient values from the interpolation lookup table, and applying the coefficient values to subsets of pixel values in a column; and d. interpolation selection means for receiving the input digital image signal input to the row interpolator means, and in response thereto, for selecting said first or second interpolation kernel for row interpolation, and for receiving the interpolated signal values from the row interpolation means, and in response thereto, for selecting said first or second interpolation kernel for column interpolation.
Claim 3
Dependent Claim 41 words
Apparatus claimed in claim 1, wherein said first interpolation kernel is for cubic convolution, and said second interpolation kernel is for replication, and wherein said interpolation selection means selects replication when the difference between successive pixel values exceeds a predetermined threshold.
Claim 4
Dependent Claim 34 words
Apparatus claimed in claim 2, wherein said interpolation kernels employ a number of pixels and said interpolation selection means maintains a selection for at least the number of pixels employed by the selected kernel.
Claim 5
Dependent Claim 38 words
Apparatus claimed in claim 2, wherein said interpolation selection means detects when a new pixel value is greater than a predetermined threshold, and if an adjacent pixel was employed in replication, employing replication on the new pixel value.

References Cited (Backward Citations)

US4468693A Cited
US4517600A Cited
JPS592483A Cited
US4578812A Cited
US4682300A Cited
US4577235A Cited
US4595958A Cited
US4605965A Cited
US4677482A Cited
US4860118A Cited
US5700232A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-04-15 1994-10-15 1995-04-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-04-15 1998-10-15 1999-04-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-04-15 2002-10-15 2003-04-16 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag