EP0367418A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Display system interpolators
Assignee: International Business Machines Corp
•
Filing: 1989-10-06
•
Granted: —
•
Expires: 2009-10-06
Abstract
Abstract An image interpolator implements an interpolation function providing real time, continuous zoom capability to an image display system. Output image pixels are obtained by interpolating the values of the colour or intensity of the 2x2 matrix of pixels surrounding the point on the input image. The disclosed arrangement employs a bi-linear interpolation algorithm implemented in the form of cascaded one-dimensional interpolation circuits. Magnification control is established so that a unit increment of the zoom controller, such as a cursor on a tablet, results in a constant increase in the degree of magnification. The coefficients required for the interpolation are generated in real time avoiding the need for time consuming table look-ups.
Inventors
- 👤 Jorge Gonzalez-Lopez
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 16:14
CPC Classifications
G; G06; G06T; G06T3/00; G06T3/40; G06T3/4007; H; H04; H04N; H04N1/00; H04N1/387; H04N1/393; H04N1/3935
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
108 words
An interpolator in or for an image display system comprising: image storage means for storing an image comprised of a plurality of picture elements - pixels - organised in two dimensions; a plurality of buffer means for storing one pixel from each position in a first dimension; means for transferring the stored image into the line buffers; coefficient generating means, responsive to an input magnification or zoom factor indication, for generating interpolation coefficients; filter means for interpolating output pixels from the line buffer in terms of the generated interpolation coefficients; and selection means for successively connecting predetermined number of the plurality of line buffers to the filter means.
Claim 2
Dependent Claim
108 words
An interpolator in or for an image display system comprising: image storage means for storing an image comprised of a plurality of picture elements - pixels - organised in two dimensions; a plurality of buffer means for storing one pixel from each position in a first dimension; means for transferring the stored image into the line buffers; coefficient generating means, responsive to an input magnification or zoom factor indication, for generating interpolation coefficients; filter means for interpolating output pixels from the line buffer in terms of the generated interpolation coefficients; and selection means for successively connecting predetermined number of the plurality of line buffers to the filter means.
Claim 3
Dependent Claim
44 words
An interpolator as claimed in claim 1, including selection means for consecutively connecting two of the plurality of line buffers to the filter means at a time and frame buffer means for storing the output of the filter means to accumulate the interpolated image.
Claim 4
Dependent Claim
76 words
An interpolator as claimed in claim 2, wherein the coefficient generating means comprises: logic means for determining the accumulated error associated with an interpolation coefficient; logic means for determining a new interpolation coefficient based on the initial interpolation coefficient and the integer interpolation increment incremented by unity, if the accumulated error is greater than or equal to zero; logic means for decrementing the accumulated error if the accumulated error is greater than or equal to zero.
Claim 5
Dependent Claim
100 words
An interpolator as claimed in claim 2, wherein the coefficient generating means comprises: register means for storing values of an initial accumulated error, an error correction term, an integer interpolation increment, and an initial interpolation coefficient; logic means for determining the accumulated error associated with an interpolation coefficient; logic means for determining a new interpolation coefficient based on the initial interpolation coefficient and the integer interpolation increment incremented by unity, if the accumulated error is greater than or equal to zero; and logic means for decrementing the accumulated error if the accumulated error is greater than or equal to zero.
Claim 6
Dependent Claim
68 words
An interpolator as claimed in any of claims 2 to 4, wherein the interpolation coefficients comprise: a first interpolation coefficient for interpolating in a first dimension; and a second interpolation coefficient for interpolating in a second dimension; and wherein the filter means comprises: a plurality of second filter means for interpolating between two pixels from one of the buffer means in response to one of the interpolation coefficients.
Claim 7
Dependent Claim
87 words
An interpolator as claimed in claim 5, wherein the plurality of second filter means are connected such that a first of the second filter means is connected to a first line buffer for interpolating in a first dimension; a second of the second filter means is connected to a second line buffer for interpolating in the first dimension; and a third of the second filter means is connected to the output of the first and second of the second filter means for interpolating in a second direction.
Claim 8
Dependent Claim
64 words
An interpolator as claimed in claim 6, wherein each of the plurality of second filter means comprises: difference means for determining the difference between the values of a first and a second pixel in the line buffer; multiplication means for determining the product of the difference and the interpolation coefficient; and addition means for adding the product and the value of the second pixel.
Claim 9
Dependent Claim
68 words
An image display system comprising: an interpolator as claimed in any preceding claim; communication means for communicating with a remote data processing system; processor means for controlling the communication means and for storing an image into the image storage means; and data entry means for entering an interpolation command and a magnification factor; the coefficient generating means being responsive to both the interpolation command and the magnification factors.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.