Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
189 words
Apparatus for generating a two-dimensional coloured display in which there is a variation of colour across the display in a predetermined manner, the colour of each pixel in the display being defined by one or more colour components, the apparatus comprising, for each colour component, a memory (20,21) for storing a pair of gradation curves (X(i), Y(i)) representing the variation in intensity of the colour component in orthogonal directions X, Y across the display; display means (9); and processing means (22-33) for determining a resultant colour component value V(i,j) for a pixel to be displayed at a location (i,j) on the display means in accordance with the following formula: V(i,j) = f[a(X(i))b(Y(j)) + c(X(i))d(Y(j))] where the pixel has coordinates i,j and k is a normalizing constant, and where a, c, are functions of X(i), b, d are functions of Y(j) and f is an output function, the functions being chosen such that V(i,j) exhibits no discontinuities for all values of X(i), Y(j), the display means being responsive to the resultant colour component values V(i,j) to display a corresponding colour at a position in the display corresponding to that pixel.
Claim 2
Dependent Claim
189 words
Apparatus for generating a two-dimensional coloured display in which there is a variation of colour across the display in a predetermined manner, the colour of each pixel in the display being defined by one or more colour components, the apparatus comprising, for each colour component, a memory (20,21) for storing a pair of gradation curves (X(i), Y(i)) representing the variation in intensity of the colour component in orthogonal directions X, Y across the display; display means (9); and processing means (22-33) for determining a resultant colour component value V(i,j) for a pixel to be displayed at a location (i,j) on the display means in accordance with the following formula: V(i,j) = f[a(X(i))b(Y(j)) + c(X(i))d(Y(j))] where the pixel has coordinates i,j and k is a normalizing constant, and where a, c, are functions of X(i), b, d are functions of Y(j) and f is an output function, the functions being chosen such that V(i,j) exhibits no discontinuities for all values of X(i), Y(j), the display means being responsive to the resultant colour component values V(i,j) to display a corresponding colour at a position in the display corresponding to that pixel.
Claim 3
Dependent Claim
22 words
Apparatus according to claim 1, wherein the formula is chosen from: V(i,j) = X(i)Y(j)/k and V(i,j) = [kX(i) + kY(j) - X(i)Y(j)]/k
Claim 4
Dependent Claim
17 words
Apparatus according to claim 1 or claim 2, wherein the processing means comprises a suitably programmed computer.
Claim 5
Dependent Claim
66 words
Apparatus according to claim 1 or claim 2, wherein the processing means comprises first, second, third and fourth look-up tables (22,23; 24,25) defining the respective functions a(Xi), b(Xi), c(Xi), and d(Xi); two multipliers (26, 27) to which outputs from the first and third look-up tables and second and fourth look-up tables are fed respectively; and an adder (28) for adding the outputs from the multipliers (26,27).
Claim 6
Dependent Claim
21 words
Apparatus according to claim 4, further comprising means (29-31) for adding a random variation to the output from the adder (28).
Claim 7
Dependent Claim
21 words
Apparatus according to claim 4 or claim 5, further comprising a normaliser (32) for normalising the output from the adder (28).