System for improving an image displayed on a display

• US 7,471,843 B2
• Filed: 06/15/2004
• Issued: 12/30/2008
• Est. Priority Date: 02/04/2004
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Messing, Dean, Kerofsky, Louis J.
• Primary Examiner(s): Le, Brian Q
• Assistant Examiner(s): TSAI, TSUNG YIN
• Application Number:
  US10/869,770
• Publication Number:
  US 20050169551A1
• Time in Patent Office: 1,659 Days
• Field of Search: 382/260, 382/309, 382/270
• US Class Current: 382/260
• CPC Class Codes: G06T 3/4015 Image demosaicing, e.g. colour filter arrays [CFA] or Bayer patterns
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2340/0457 Improvement of perceived resolution by subpixel rendering
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607

Abstract

A system for improving the an image displayed on a display.

Claims

1. A method for filtering an image for displaying said image on a display comprising:

(a) filtering said image using a set of filters that reduce an error metric, wherein said filters are based upon a constrained optimization that includes at least one constraint based on a two-dimensional geometric parameter of said display, and wherein said error metric is perceptually weighted quadratic of a two-dimensional transform of a function having the form E_n=M_ná

_n−

Cx_n, where “

E”

represents said error metric, “

x”

represents samples from said image, “

á

”

represents scalar display subpixel values, “

n”

denotes subpixel locations, “

C”

represents an operation that converts x_n into an opponent color space, and M_n is a function of C_n of the form M_n=aC_n mod a, “

a”

being the number of display subpixels per pixel;

(b) re-sampling said filtered image to a lower resolution;

(c) displaying said re-sampled image on said display.

2. The method of claim 1 wherein said set of filters includes more than 9 different re-sampling filters.

3. The method of claim 2 wherein said filters filter said luminance information and attenuate at least a portion of lower frequency chromatic information with respect to at least a portion of higher frequency chromatic information resulting from said filtering of said luminance information.

4. The method of claim 2 wherein said filters are based upon a perceptual error metric.

5. The method of claim 2 wherein said display is a liquid crystal display.

6. The method of claim 5 wherein said display includes a pattern of subpixels in a horizontal direction that are different than the pattern of subpixels in a vertical direction.

7. The method of claim 2 wherein said re-sampling and said filtering are performed in the same operation.

8. The method of claim 2 wherein said re-sampling is performed after said filtering.

9. The method of claim 2 wherein a plurality of said filters are one-dimensional.

10. The method of claim 2 wherein a plurality of said filters are two-dimensional.

11. The method of claim 1 wherein said display includes a two-dimensional sub-pixel geometry.