Terminal independent color memory for a digital image display system

• US 4,439,759 A
• Filed: 05/19/1981
• Issued: 03/27/1984
• Est. Priority Date: 05/19/1981
• Status: Expired due to Term

• Current Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Original Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Inventors: Fleming, James R., Frezza, William A., Soloway, Gerald S.
• Primary Examiner(s): Curtis, Marshall M.
• Application Number:
  US06/265,195
• Time in Patent Office: 1,043 Days
• Field of Search: 340/703, 340/701, 340/717, 340/747, 340/750, 340/726, 340/709, 340/723
• US Class Current: 345/601
• CPC Class Codes: G09G 5/06 using colour palettes, e.g. look-up tables

Abstract

The present terminal independent color memory for a digital image display system provides for inter-system compatability, color display systems generally having varying modes of access to color memories, varying color memory capacities, and features such as blinking implemented in varying ways. The data processor (1) of the present system may access color memory (6a) of video controller (6) or color values stored in permanent memory (9) or random access memory (10), responsive to the same command language. The present data processor (1) is also capable of entering color data values comprising color hues and gray levels into color memory for use in a terminal independent manner. Multiple process chained blinking from a particular color to a particular color is also provided by the present processor, the several processes in time-delayed relationship to one another.

Claims

1. In a digital image display system:

a memory for storing color data values;

processing means responsive to a predetermined command and data sequence comprising at least one command, the processing means decoding the predetermined command and data sequence, the predetermined command and data sequence selecting one of a plurality of modes of access to color data values, the modes comprising

a first mode of access wherein an in-use foreground color is directly specified as a color data value;

a second mode of access wherein the in-use foreground color is specified as an index into the color memory; and

a third mode of access wherein the in-use foreground color and an in-use background color are specified as indexes into the color memory; and

display means responsive to the processing means, the display means displaying the colors associated with the color data values accessed by the selected mode.

2. A digital image display system comprising:

a color memory for storing color data values;

processing means responsive to predetermined command and data sequences, the processing means, responsive to a first command, selecting a mode of access to the color memory; and

responsive to a second command, setting a color data value in the color memory; and

display means responsive to the processing means, the display means displaying a color associated with the color data value accessed by the selected mode.

3. A display system as recited in claim 2, wherein the processing means responsive to a second command sets plural color data values in color memory.

4. In a video image display system having a color memory, a method for displaying a color image in a terminal independent manner responsive to commands and data received from a command and data source, the method comprising the steps of:

receiving commands and data from the command and data source;

reading a first command for selecting a mode of access to the color memory, and responsive to data following the first command, selecting the mode of access to the color memory;

reading a second command for setting color data values in the color memory and, responsive to data following the second command, setting the color data values in the color memory,

reading a third command for accessing color data values in the color memory, and

displaying a color image associated with the color data values accessed by the third command on a video display terminal.

5. A digital image display system comprising:

a color map memory for storing color data values;

processing means for storing color data values in the color map memory and accessing color data values stored in the color map memory, the color data values comprising 2^N /2 gray level data values equally spaced between black and white, where N is the number of bits in a color entry address of the color map memory and the processing means storing the gray level data values in one half of the color map memory, the color data values further comprising 2^N /2 hue data values equally spaced about a 360 degree hue circle wherein primary colors red, green, and blue are located in 120 degree relationship to one another and the processing means storing the hue data values in another half of the color map memory, the processing means upon command accessing color data values stored in the color map memory; and

display means responsive to the processing means for displaying an image associated with accessed color data values.

6. A digital image display system comprising:

a color map memory for storing color data values;

processing means for storing hue color data values in the color map memory and accessing color data values stored in the color map memory, the hues being equally spaced about a 360 degree hue circle wherein primary colors red, green, and blue are located in 120 degree relationship to one another, and where h is a desired hue color data value, n is a desired number of hue color data values, angle of h is determined by (j-1)×

360 degrees divided by n, where j is an integer between 1 and n, P₁ is the closest primary color to the angle of h, P₂ is the next closest primary color to the angle of h, and P₃ is the furthest primary color from the angle of h, the identity of P₁, P₂, and P₃ being assigned among the primary colors, the processing means setting the binary value of P₁ in the color map memory as all 1 bits, setting the binary value of P₃ in the color map memory as all 0 bits, and setting in the color map memory the normalized and rounded binary value of P₂ resulting from the equation;

##EQU2## and upon command accessing color data values stored in the color map memory; and

display means responsive to the processing means for displaying an image associated with accessed color data values.

7. A digital image display system comprising:

a color memory for storing color data values;

processing means responsive to a particular command and data sequence providing a blinking of certain picture element data from one particular color specified by the data sequence to another particular color specified by the data sequence by periodically changing color data values in the color memory, multiple color blinking processes being provided responsive to multiple commands, each process subsequent to a first process being in delay relationship to the next previous process; and

a display means for displaying the multiple color blinking responsive to the processing means.

8. A display system as recited in claim 7 wherein the processing means determines the time interval each particular color is displayed during a blinking cycle responsive to the command and data sequence.

9. In a digital image display system having a color memory, a method for providing a blinking of certain picture element data from one particular color to another particular color, the color blinking method initiated by the reception of a particular command and data sequence, the color blinking method characterized by the steps of:

specifying multiple color blinking processes, each color blinking process including providing a blinking of certain picture element data from one particular color specified by the data sequence to another particular color specified by the data sequence by periodically changing color data values in the color memory;

specifying a delay interval, if desired, between the processes; and

displaying the multiple color blinking.

10. A method for providing color blinking as recited in claim 9 further characterized by the steps of

specifying a particular time interval a particular color is displayed during a blinking cycle of a particular color blinking process.