Color display

• US 5,254,977 A
• Filed: 07/13/1992
• Issued: 10/19/1993
• Est. Priority Date: 06/12/1989
• Status: Expired due to Term

• Current Assignee: Fujifilm Electronic Imaging Ltd. (Fujifilm Holdings Corporation)
• Original Assignee: Crosfield Electronics Ltd. (Fujifilm Holdings Corporation)
• Inventors: MacDonald, Lindsay W.
• Primary Examiner(s): Weldon, Ulysses
• Assistant Examiner(s): CHOW, DOON Y
• Application Number:
  US07/911,382
• Time in Patent Office: 463 Days
• Field of Search: 340/701, 340/703, 340/799, 340/798, 358/81, 358/78, 358/89, 395/131
• US Class Current: 345/591
• CPC Class Codes: G06F 3/04845 for image manipulation, e.g. dragging, rotation, expansion or change of colour
• CPC Class Codes: G09G 5/06 using colour palettes, e.g. look-up tables

Abstract

A method of displaying a selected section of an N-dimensional color space uses two memories (14,16). The first memory (14) stores memory addresses of the second (16). The second memory (16) stores data defining color at addresses corresponding to the selected section and background color at all other addresses. The defined colors and background are output to a display (11) so that the background areas blend with the existing background and only the color of the selected section is redrawn not the whole image.

Claims

1. A method of displaying in respective regions of a display, colours defined by a selected section of a colour space defined by N orthogonal axes, the method comprising:

a) a first preliminary step of determining and storing data defining a set of displayable colours within the colour space, and a second preliminary step of storing addresses of a colour memory in locations of a frame tore corresponding to pixels of each region, wherein each region is defined by an array of pixels for each of which the same colour memory address is stored, the addresses for each region being different;

b) subsequently;

i) determining the section of the colour space to be displayed;

ii) storing, at each address in the colour memory corresponding to a region which is to display a colour of the selected section, data defining the colour, and at each address corresponding to an unused region, data defining a common background colour by downloading data selected from the previously generated colour data into the colour memory; and

iii) displaying on the display the colours defined in the color memory in the corresponding regions; and

c) repeating step b) without repeating step a) so as to display other selected sections of the colour space.

2. A method according to claim 1, in which the N-dimensional colour space is a three dimensional colour space.

3. A method according to claim 1, wherein the section of the colour space is a two dimensional plane.

4. A method according to claim 1, wherein the regions are spaced apart.

5. Apparatus for displaying, in respective regions of a display, colours defined by a selected section of a colour space defined by N orthogonal axes, the apparatus comprising:

a display;

a frame store;

a colour memory;

a processor;

a main memory in which is stored data defining a set of colours within the colour space which may be displayed, wherein said processor is adapted to download selected colour data from said main memory to said colour memory in response to the selection of a corresponding section of said colour space; and

an input device,

wherein data is stored in locations of the frame store corresponding to pixels of each region defining respective addresses of the colour memory, wherein each region is defined by an array of pixels for each of which the same colour memory address is stored, the addresses for each region being different, wherein the processor responds to instructions from an operator via the input device to determine the section of the colour space to be displayed, the processor storing, at each address in the colour memory corresponding to a region which is to display a colour of a selected plane, data defining the colour, and, at each address corresponding to an unused region, data defining a common background colour, whereby the display displays the colours defined in the colour memory in the corresponding regions, and wherein upon other sections of said colour space being selected by the operator, the processor reloads said colour memory without changing the content of said frame store.

6. Apparatus according to claim 5, wherein said colour memory includes a look-up table.

7. Apparatus according to claim 5, wherein the display comprises a cathode ray tube video monitor.