Bit plane partitioning for graphic displays

• US 5,083,257 A
• Filed: 11/23/1990
• Issued: 01/21/1992
• Est. Priority Date: 04/27/1989
• Status: Expired due to Fees

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Kennedy, Peter D.
• Primary Examiner(s): Harkcom, Gary V.
• Assistant Examiner(s): Bayerl, Raymond J.
• Application Number:
  US07/617,488
• Time in Patent Office: 424 Days
• Field of Search: 364/518, 364/521, 340/703, 340/734, 340/799, 340/798
• US Class Current: 345/602
• CPC Class Codes: G09G 5/06 using colour palettes, e.g. look-up tables
• CPC Class Codes: G09G 5/395 Arrangements specially adapted for transferring the contents of the bit-mapped memory to the screen G09G5/399 takes precedence

Abstract

A bit plane partitioned graphics display system prioritizes large numbers of classes of information prior to relaying the information to the color lookup table. This allows the color lookup table to process only 12 or less bits of information at a time. The graphics display system comprises n bit planes for storing the information to be displayed and outputting a pixel word having n bits, where n is the number of bits of information input to the graphics display system, bit plane masking for altering groups of the n bit planes without affecting the information on the other bit planes, pixel word processor for modifying bits of each pixel word output from the n bit-planes, a prioritizer for determining which information has the highest priority and outputting only the highest prioritized bits of information in 12 or less bits, intermediate color lookup tables for converting each group of bits in each pixel word into a set of bits that will produce the desired color, a color lookup table for outputting red, green, or blue color signals based upon the prioritizer output, digital-to-analog converters for converting these color signals into analog form, and a graphics display screen for displaying the red, green, and blue color analog signals.

Claims

1. A graphics display system for displaying large numbers of classes of information comprising:

bit plane means for storing a plurality of bits of information, said bit plane means having a predetermined number of n bit planes corresponding to said plurality of bits of information;

said n bit planes arranged according to a priority of visual importance of said bits of information;

said bit plane means generating a pixel word having n bits of information;

said pixel word arranged into sets of information, said sets of information arranged in a priority corresponding to said priority of visual importance of said bits of information;

pixel word processor means coupled to said bit plane means to receive said pixel word;

said pixel word processor means for altering selective bits of information of said pixel word;

prioritizer means coupled to said pixel word processor means to receive said pixel word;

said prioritizer means for selecting the highest prioritized set of said sets of information and outputting said highest prioritized set of said sets of information;

said prioritizer means including;

a selector switch;

a plurality of intermediate color lookup table means coupled in parallel between said bit plane means and said selector switch; and

said plurality of intermediate color lookup table means for generating a p-bit (where p is an integer number representing the number of bits of information) definition signal defining a p-bit code corresponding to colors within said lookup table means for the highest prioritized information within each of said sets of information;

lookup table means coupled to said prioritizer means to receive said highest prioritized set;

said lookup table means for generating a plurality of sets of color information corresponding to said highest prioritized set, each of said plurality of sets representing a primary color displayed on the graphics display system;

display screen means coupled to said lookup table means to receive said plurality of sets of color information; and

said display screen means for generating a graphics display picture.

2. A graphics display system for displaying large numbers of classes of information according to claim 1 wherein said display system further comprises:

bit plane masking means coupled to said bit plane means;

said bit plane masking means for writing to at least one of said n bit planes at a time without disturbing information of other of said n-bit planes; and

said bit plane masking means arranging said at least one of said n-bit planes into groups of information to be altered.

3. A graphics display system for displaying large numbers of classes of information according to claim 1 wherein said prioritizer means comprises:

a plurality of determinant means coupled to said bit plane means;

said plurality of determinant means receiving one each of said prioritized sets of information of said pixel word;

said plurality of determinant means for determining which of said prioritized sets of information includes meaningful information;

said plurality of determinant means generating a plurality of determinant outputs;

priority logic means coupled to said plurality of determinant means to receive said plurality of determinant outputs;

said priority logic means for generating a priority output corresponding to the highest prioritized of said prioritized sets of information containing meaningful information;

said selector switch coupled to said bit plane means to receive said prioritized sets of information of said pixel word, and further coupled to said priority logic means to receive said priority output;

said selector switch for relaying one of said sets of information from said bit plane means to said look up table means;

said selector switch selecting said relayed one of said sets of information determined according to said priority output; and

said selector switch coupled to said look up table means to supply said selected one of said sets of information.

4. A method for displaying large numbers of classes of information that are defined by, for example, 16, 24, or 32 bits, in a graphics display system when using a graphics display color lookup table capable of processing significantly less bits of information, said method comprising the steps of:

storing the information in n bit planes prioritized according to the importance of information to be displayed, where n is the integer number of bits of information to be displayed;

generating n-bit pixel words having a plurality of prioritized sets of information within each n-bit pixel word, each of said sets of information having less bits of information than said n-bit pixel words, said bits of information of said sets of information corresponding to the number of the bits of the graphics display color lookup table;

relaying said n-bit pixel words to a pixel word processor;

altering selective bits of said n-bit pixel words within said pixel word processor;

relaying said altered n-bit pixel words to a prioritizer;

determining which set of said sets of information of said n-bit pixel words has the highest prioritized information;

said step of determining including the steps of;

relaying said n-bit pixel words in parallel to a plurality of determinants and to a plurality of intermediate lookup tables, wherein one each of said sets of information are relayed to one each of both of said plurality of determinants and said plurality of intermediate lookup tables;

determining within said determinants which of sets of information contain information to be displayed;

generating a one-bit signal, within each of said plurality of determinants when a respective one of said sets of information contains meaningful information; and

outputting said highest prioritized set of information to the color lookup table.

5. A method for displaying large numbers of classes of information, that are defined by, for example, 16, 24, or 32 bits, in a graphics display system when using a graphics display color lookup table capable of processing significantly less bits of information according to claim 4, wherein said step of determining which set further comprises the steps of:

relaying said one-bit signals to a priority logic circuit;

generating within said priority logic circuit a priority signal which corresponds to the highest prioritized one of said sets of information having significant information;

relaying said priority signal to a selector switch;

determining within said plurality of intermediate lookup tables a plurality of color code signals for the highest prioritized information within each of said sets of information;

relaying said plurality of color code signals to said selector switch;

determining within said selector switch the highest prioritized one of said sets of information; and

outputting said highest prioritized one of said sets of information to the color lookup table.

6. A prioritizer for a graphics display system where the graphics display system must display large numbers of classes of information but may only process smaller numbers of bits of information within the color lookup table, and the graphics display system includes n bit planes outputting a pixel word arranged in prioritized sets of information, where n is the number of bits of information to be displayed by the graphics display system, said prioritizer comprising:

a plurality of determinant means coupled in parallel to said bit planes;

each of said plurality of determinant means receiving one each of said prioritized sets of information of said pixel word;

each of said plurality of determinant means for generating an output when the received prioritized set of information contains information for display;

priority logic means coupled to each of said plurality of determinant means to receive said output;

said priority logic means for generating a priority output corresponding to the highest prioritized of said prioritized sets of information which contains information for display;

a plurality of intermediate color lookup table means coupled in parallel to said bit planes to receive one each of said prioritized sets of information of said pixel word;

said plurality of intermediate color lookup table means for generating a plurality of n-bit definition signals defining n-bit codes corresponding to colors within the color lookup table for the highest prioritized information within each of said sets of information;

selector switch coupled to said plurality of intermediate color lookup table means to receive said n-bit definition signals, and further coupled to said priority logic means to receive said priority output;

said selector switch for relaying one of said n-bit definition signals to the color lookup table;

said selector switch selecting said relayed one of said n-bit definition signals according to said priority output; and

said selector switch coupled to the color lookup table to supply said selected one of said n-bit definition signals.