John E Pittas

US Patent:

60880457, Jul 11, 2000

Filed:

Jul 22, 1991

Appl. No.:

7/733950

Inventors:

Leon Lumelsky - Stamford CT
Sung Min Choi - White Plains NY
Alan Wesley Peevers - Berkeley CA
John Louis Pittas - Bethel CT

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G09G 536

US Classification:

345509

Abstract:

An image display system (10) includes an image buffer (20,22) having a plurality of addressable locations for storing image pixel data. The system further includes circuitry (24,34,36) coupled to an output of the image buffer for converting image pixel data read therefrom to electrical signals for driving an image display (18). The circuitry is responsive to signals generated by an image display controller (16) for generating one of a plurality of different timing formats for the electrical signals for driving an image display having a specified display resolution. The apparatus further includes circuitry (40,42) for configuring the image buffer in accordance with the specified display resolution. The image buffer is configurable, by example, as two, 2048 location by 1024 location by 24-bit buffers and one 2048 location by 1024 location by 16-bit buffer; or as two, 2048 location by 2048 location by 24-bit buffers and one 2048 location by 2048 location by 16-bit buffer. Each of the 24-bit buffers store R,G,B pixel data and the 16-bit buffers each store a color index (CI) value and an associated window identifier (WID) value.

US Patent:

54206081, May 30, 1995

Filed:

Jan 27, 1994

Appl. No.:

8/187823

Inventors:

Sung M. Choi - White Plains NY
Leon Lumelsky - Stamford CT
Alan W. Peevers - Peekskill NY
John L. Pittas - Bethel CT

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G09G 102

US Classification:

345186

Abstract:

A display system is described which includes storage for receiving a compressed pixel image manifesting at least a pair of encoded colors and a bit MASK that defines which pixels of a pixel subset of the pixel image receive one of the colors. The system comprises a plurality of memory modules. The pixels in the subset are interleaved in the memory modules. A generator is provided for applying signals to cause data to be written into each of modules in parallel. Register means are provided for applying data manifesting the encoded colors to the modules. Control apparatus is responsive to the MASK bits for controlling the generator to write the encoded color data, in parallel and in a single memory cycle, into all pixel positions of the subset that are designated for the color(s) by MASK bit position values.

US Patent:

53510674, Sep 27, 1994

Filed:

Jul 22, 1991

Appl. No.:

7/733766

Inventors:

Leon Lumelsky - Stamford CT
Sung M. Choi - White Plains NY
Alan W. Peevers - Berkeley CA
John L. Pittas - Bethel CT

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G09G 102
G09G 106

US Classification:

345191

Abstract:

Method and apparatus for implementing a raster graphic display video data path that provides arbitrary mixing of a plurality of images. The video data path is highly parallelized, and employs parallel devices operating under the control of a set of look-up tables. The look-up tables are loadable from a controller, such as a host workstation. The raster graphic display video data path functions with unlimited screen resolutions, and also enables a variety of different pixel data formats from a potentially large number of different sources. Outputs from several image sources are mixed under the control of the host workstation, with a resultant pixel value being based on (a) a combined translucency coefficient (alpha) of the images, for each image source, and (b) a window identification number assigned by the host workstation. Pixel value conversion to a common predetermined format provides coherency between pixel values generated by a number of different image sources, such as HDTV and graphics servers. A separate frame buffer is allocated for each of the sources.

US Patent:

51969246, Mar 23, 1993

Filed:

Jul 22, 1991

Appl. No.:

7/733576

Inventors:

Leon Lumelsky - Stamford CT
Calvin B. Swart - Poughkeepsie NY
John L. Pittas - Bethel CT
Sung M. Choi - White Plains NY
Alan W. Peevers - Berkeley CA

Assignee:

International Business Machines, Corporation - Armonk NY

International Classification:

H04N 5202

US Classification:

358 32

Abstract:

An image display system includes an input to a source (10, 12, 14) of image pixel data wherein each pixel is expressed as an M-bit value within a non-linear range of values. A first LUT (16) is coupled to an output of the source for converting each M-bit pixel value to an N-bit value within a linear range of values. An image memory, or frame buffer (18), has an input coupled to an output of the first LUT for storing the N-bit pixel values. The system further includes a second LUT (20) coupled to an output of the frame buffer for converting N-bit pixel values output by the frame buffer to P-bit pixel values within a non-linear range of values. The converted values are subsequently applied to a display (24). In an exemplary embodiment, the first LUT stores gamma corrected pixel values and the second LUT stores inverse gamma corrected pixel values. Preferably the second LUT stores a plurality of sets of inverse gamma corrected pixel values.