Multi-pixel addressing method for video display drivers

• US 8,681,185 B2
• Filed: 03/04/2010
• Issued: 03/25/2014
• Est. Priority Date: 03/05/2009
• Status: Active Grant

• Current Assignee: Ostendo Technologies Inc.
• Original Assignee: Ostendo Technologies Inc.
• Inventors: Guncer, Selim E.
• Primary Examiner(s): SHENG, TOM V
• Application Number:
  US12/717,365
• Publication Number:
  US 20100225679A1
• Time in Patent Office: 1,482 Days
• Field of Search: 345/204, 345/690, 348/254, 348/674, 704/204
• US Class Current: 345/690
• CPC Class Codes: G09G 2340/02 Handling of images in compressed format, e.g. JPEG, MPEG
• CPC Class Codes: G09G 3/2022 using sub-frames
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
• CPC Class Codes: G09G 3/3625 using active addressing

Abstract

A video display system is described which is formed by an array of pixels comprised of fast responding light elements, row select and column select switches and pixel data drivers, and a computation subsystem which generates the control signals for the select lines and the video data. The overall system reconstructs the intended image or video to be displayed through successively displaying subframes of images corresponding to orthogonal image basis function components of the original image acting on a grouping of pixels selected using multiple row and column lines. The resultant system is an architecture which enables one to implement certain video decompression techniques directly on the light elements, as opposed to implementing these techniques in digital processing, and can have a considerably reduced raw video data requirement than a system in which pixels are addressed individually, and enables higher dynamic range to be achieved with similar digital-analog-converter specifications. Embodiments with LED based displays are described herein.

Claims

1. A method of displaying an image having M by N pixels, comprising;

selecting each of a plurality of macro-pixel groupings collectively forming the M by N pixel display;

generating patterns corresponding to on-off switch states of Walsh transform type orthogonal basis functions for each macro-pixel;

determining image coefficients for respective patterns;

for image coefficients which are negative, reversing the pattern from blocking to passing state (‘

0’

to ‘

1’

) and vice versa by inverting the pattern for the respective orthogonal basis functions and using the absolute value for the respective image coefficient in the following correction of the zero image coefficient;

cancelling the averaging artifact which arises from using patterns corresponding to non-orthogonal basis functions which multiply by 0 or +1 instead of −

1 or +1 by correcting the zero image coefficient applicable to the entire macro-pixel by subtracting one half of the sum of the image coefficients applicable to all patterns before controlling pixel illumination;

controlling the pixel illumination within a macro-pixel using patterns responsive to an image coefficient for the respective pattern using the corrected zero image coefficient.

2. The method of claim 1 wherein when one half of the sum of the image coefficients are greater than the zero coefficient, then spatial frequency filtering to eliminate some non-zero coefficients and respective patterns employed to keep one half of the sum of the non-zero coefficients equal to or smaller than the zero coefficient.

3. The method of claim 1 wherein when one half of the sum of the image coefficients are greater than the zero coefficient, then reducing the number of pixels in the macro-pixel grouping to keep one half the sum of non-zero coefficients equal to or smaller than the zero coefficient.

4. The method of claim 1 wherein data defining the image is in digital form and lower order image coefficients have a greater bit precision than higher order image coefficients.