Tandy Corporation

Ast Research, Inc.

Carl K Wakeland

Dale Chatham

John M Prickett

A computer system having dual paths for controlling a peripheral device electrically associated with a host computer. The peripheral device is electrically connected to the host computer and to an independent control circuit. Control inputs for the peripheral device and data and/or control inputs for the host computer are generated by a keyboard or other input device and transmitted to an input controller which directs certain data and/or control inputs to the host computer for processing and directs certain peripheral device control inputs to a state machine for the generation of peripheral device control signals. In such a manner, the independent control circuit provides for the control of the peripheral device while the host computer may process data unrelated to the control of the peripheral device. In one aspect, control of the peripheral device may be effected by both the host computer and the independent control circuit. Accordingly, in this aspect, the independent control circuit further comprises an arbitrator which resolves any control conflicts that arise between the host computer and the independent control circuit.

Adjusting the volume by a keyboard via an independent control circuit, independent of a host computer

Dual path computer control system

A palette for converting video data encoded in multiple YUV and RGB formats into a configuration suitable for transmission to a display and a multimedia system incorporating the same. The palette selectively converts video data encoded into a five bit luminance component for each of four successive pixel elements, a first five bit chrominance component for the four successive pixel elements and a second five bit chrominance component for the four successive pixel elements into a eight bit red, green and blue components for the pixel elements, converts video data encoded in an eight bit luminance component for each of two successive pixel elements and first and second eight bit luminance components for the two successive pixel elements into eight bit red, green and blue components for the pixel element, converts video data encoded in four data bits for a pixel element into six bit red, green and blue components for the pixel element and converts video data encoded in multiple RGB mode, including 555, 565 and 888 modes, into eight bit red, green and blue components.

Multiple extended mode supportable multimedia palette and multimedia

A VGA controller having an overlay mode for displaying images formed from selective components of multiple image planes. A first image and a second image overlaying the first image are interleaved into three of four bit planes of a dynamic random access memory. When displaying the image, the controller will simultaneously read from the first and second images. If the value of the second image is non-zero, then the second image is displayed. Otherwise, the first image is displayed.

VGA controller for displaying images having selective components from

Method and apparatus within a multimedia system for digitally decoding video pixel data. The pixel data is decoded to 24 bits per pixel from a compressed 8 bits per pixel format. The compressed pixel data is deformatted into its separate luminance and chrominance components. The components are then differentially expanded and assigned to associated pixel elements. Predominant color transitions are designated to determine the pixel location where the chrominance components change. An interpolated chrominance component may be inserted at these color change locations to smooth out the color transitions.

Method and apparaus for decoding encoded video data

A method for merging first and second digital video signals generated by first and second video controllers, respectively, for merged transmission to a digital video decoder. The first video controller transmits the first digital video signal to the decoder while monitoring the signal to detect a luminance component which designates the boundary between a first image constructable from the first video signal and a second image constructable from the second video signal. When the luminance component is detected, a colorkey signal is generated by the first video controller and transmitted to the second video controller to initiate transmission of the second digital video signal to the decoder in place of the first digital video signal. The first video controller continues to monitor the first video signal until the absence of the luminance component is detected. The first video controller then transmits a second colorkey signal to the second video controller to terminate the second digital video signal and transmission of the first digital video signal to the decoder recommences.

Method and apparatus for merging video data signals from multiple

Method and apparatus for encoding full color video data signals and a protocol for encoding the same in a storage medium. Each pixel of a full color video image is converted into a single 8 bit luminance and multiple 8 bit chrominance components. The 8 bit luminance component is differentially compressed into 5 bits while the chrominance components are subsampled for every four pixels of the video image before being differentially compressed. The differentially compressed subsampled chrominance components and the differentially compressed luminance components are then assembled into a video data signal related to the full color image.

Growing community of inventors

Bedford, TX, United States of America

Carl K Wakeland