Correcting method, correcting apparatus and method for establishing color performance database for display apparatus
A correcting method for a display apparatus is provided. For N original grayscale combinations, color performances of the display apparatus are respectively measured to generate N measurement results. A set of color blending equations are utilized for M original grayscale combinations according to the N measurement results to generate M blended results. From the N measurement results and the M blended results, P color performances respectively most approximate to P target performances are identified. The P target color performances correspond to P target grayscale combinations. The P color performances correspond to P original grayscale combinations in the (N+M) original grayscale combinations. A look-up table for correcting the display apparatus is established according to the P target grayscale combinations and the P corresponding original grayscale combinations.
1. A correcting method for a display apparatus, implemented in a non-transitory computer readable medium, comprising:
a) measuring respective color performances of the display apparatus for N original grayscale combinations, to generate N measurement results, where N is a positive integer greater than 1;
b) utilizing a set of color blending equations for M original grayscale combinations according to the N measurement results to generate M blended results, where M is a positive integer;
c) establishing a color performance database comprising (N+M) color performances according to the N measurement results and the M blended results;
d) identifying P color performances respectively most approximate to a P predetermined target color performances from the color performance database, wherein P is a positive integer; wherein, the P target color performances correspond to P target grayscale combinations, and the identified P color performances correspond to P original grayscale combinations in the (N+M) original grayscale combinations; and
e) establishing a look-up table (LUT) according to the P target grayscale and the corresponding P original grayscale combinations; and
f) controlling a driver circuit of the display apparatus to send out an original grayscale combination corresponding to a target grayscale combination determined using the LUT with an inputted grayscale combination as an index,
wherein a maximum grayscale value that the display apparatus supports is G MAX , and the N original grayscale combinations comprises (0, 0, 1), (0, 0, 2) . . . (0, 0, G MAX ), (0, 1, 0), (0, 2, 0) . . . (0, G MAX , 0), (1, 0, 0), (2, 0, 0) . . . (G MAX , 0, 0) and (0, 0, 0),
wherein one of the M original grayscale combinations is (R 0 , G 0 , B 0 ), the blended result is (X′,Y′,Z′), and the set of color blending equations comprises:
X′=X ( R 0 ,0,0)+ X (0, G 0 ,0)+ X (0,0, B 0 ),
Y′=Y ( R 0 ,0,0)+ Y (0, G 0 ,0)+ Y (0,0, B 0 ),
Z′=Z ( R 0 ,0,0)+ Z (0, G 0 ,0)+ Z (0,0, B 0 ),
wherein, X(R 0 ,0,0), Y(R 0 ,0,0) and Z(R 0 ,0,0) represent the color performances of an original grayscale combination (R 0 ,0,0) in a CIE XYZ color space; X(0,G 0 ,0), Y(0,G 0 ,0) and Z(0,G 0 ,0) represent the color performances of an original grayscale combination (0,G 0 ,0) in the CIE XYZ color space; and X(0,0,B 0 ), Y(0,0,B 0 ) and Z(0,0,B 0 ) represent the color performances of an original grayscale combination (0,0,B 0 ) in the CIE XYZ color space.
2. The correcting method according to claim 1 , wherein a maximum grayscale value that the display apparatus supports is G MAX , and the N original Grayscale combinations comprises (0, 0, 1), (0, 0, 2) . . . (0, 0, G mAx ), (0, 1, 0), (0, 2, 0) . . . (0, G MAX , 0), (1, 0, 0), (2, 0, 0) . . . (G MAX , 0, 0), (0, 0, 0), (1, 1, 1) . . . (G MAX , G MAX , G MAX ).
3. The correcting method according to claim 2 , wherein a one of the M original grayscale is (R 0 ,G 0 ,B 0 ); the blended result is (X′,Y′,Z′); the measurement result X′ is generated according to X(R 0 ,0,0), X(0,R 0 ,0), X(0,0,R 0 ), X(R 0 ,R 0 ,R 0 ), X(0,G 0 ,0), X(G 0 ,0,0), X(0,0,G 0 ), X(G 0 ,G 0 ,G 0 ), X(0,0,B 0 ), X(B 0 ,0,0), X(0,B 0 ,0) and X(B 0 ,B 0 ,B 0 ); the measurement result Y′ is generated according to Y(R 0 ,0,0), Y(0,R 0 ,0), Y(0,0,R 0 ), Y(R 0 ,R 0 ,R 0 ), Y(0,G 0 ,0), Y(G 0 ,0,0), Y(0,0,G 0 ), Y(G 0 ,G 0 ,G 0 ), Y(0,0,B 0 ), Y(B 0 ,0,0), Y(0,B 0 ,0) and Y(B 0 ,B 0 ,B 0 ); the measurement result Z′ is generated according to Z(R 0 ,0,0), Z(0,R 0 ,0), Z(0,0,R 0 ), Z(R 0 ,R 0 ,R 0 ), Z(0,G 0 ,0), Z(G 0 ,0,0), Z(0,0,G 0 ), Z(G 0 ,G 0 ,G 0 ), Z(0,0,B 0 ), Z(B 0 ,0,0), Z(0,B 0 ,0) and Z(B 0 ,B 0 ,B 0 ); X(R 0 ,0,0), Y(R 0 ,0,0) and Z(R 0 ,0,0) represent the color performances of an original grayscale combination (R 0 ,0,0) in the CIE XYZ color space; X(0,G 0 ,0), Y(0,G 0 ,0) and Z(0,G 0 ,0) represent the color performances of an original grayscale combination (0,G 0 ,0) in the CIE XYZ color space; X(0,0,B 0 ), Y(0,0,B 0 ) and Z(0,0,B 0 ) represent the color performances of an original grayscale combination (0,0,B 0 ) in the CIE XYZ color space; X(R 0 ,R 0 ,R 0 ), Y(R 0 ,R 0 ,R 0 ) and Z(R 0 ,R 0 ,R 0 ) represent the color performances of an original grayscale combination (R 0 ,R 0 ,R 0 ) in the CIE XYZ color space; X(G 0 ,G 0 ,G 0 ), Y(G 0 ,G 0 ,G 0 ) and Z(G 0 ,G 0 ,G 0 ) represent the color performances of an original grayscale combination (G 0 ,G 0 ,G 0 ) in the CIE XYZ color space; X(B 0 ,B 0 ,B 0 ), Y(B 0 ,B 0 ,B 0 ) and Z(B 0 ,B 0 ,B 0 ) represent the color performances of an original grayscale combination (B 0 ,B 0 ,B 0 ) in the CIE XYZ color space; X(0,R 0 ,0), Y(0,R 0 ,0) and Z(0,R 0 ,0) represent the color performances of an original grayscale combination (0,R 0 ,0) in the CIE XYZ color space; X(0,0,R 0 ), Y(0,0,R 0 ) and Z(0,0,R 0 ) represent the color performances of an original grayscale combination (0,0,R 0 ) in the CIE XYZ color space; X(G 0 ,0,0), Y(G 0 ,0,0) and Z(G 0 ,0,0) represent the color performances of an original grayscale combination (G 0 ,0,0) in the CIE XYZ color space; X(0,0,G 0 ), Y(0,0,G 0 ) and Z(0,0,G 0 ) represent the color performances of an original grayscale combination (0,0,G 0 ) in the CIE XYZ color space; X(B 0 ,0,0), Y(B 0 ,0,0) and Z(B 0 ,0,0) represent the color performances of an original grayscale combination (B 0 ,0,0) in the CIE XYZ color space; and X(0,B 0 ,0), Y(0,B 0 ,0) and Z(0,B 0 ,0) represent the color performances of an original grayscale combination (0,B 0 ,0) in the CIE XYZ color space.
4. The correcting method according to claim 3 , wherein the set of color blending equations comprise:
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5. The correcting method according to claim 1 , wherein step (d) comprises evaluating a difference ΔE between a first color performance (X 1 ,Y 1 ,Z 1 ) and a second color performance (X 2 ,Y 2 ,Z 2 ) in the CIE XYZ color space according to an equation:
Δ E =√(( X 1 −X 2 )2+( Y 1 −Y 2 )2+( Z 1 −Z 2 )2).
6. The correcting method according to claim 1 , wherein step (d) comprises evaluating a difference ΔE between a first color performance (L 1 ,a 1 ,b 1 ) and a second color performance (L 2 ,a 2 ,b 2 ) in a CIE Lab color space according to an equation:
Δ E =√(( L 1 −L 2 )2+( a 1 −a 2 )2+( b 1 −b 2 )2).
7. A method for establishing a color performance database for a display apparatus, implemented in a non-transitory computer readable medium, comprising:
a) for N grayscale combinations, measuring respective color performances of the display apparatus to generate N measurement results, where N is a positive integer greater than 1;
b) utilizing a set of color blending equations for M grayscale combinations according to the N measurement results to generate M blended result, where M is a positive integer; and
c) establishing a color performance database comprising (N+M) color performances according to the N measurement results and the M blended results,
wherein a maximum grayscale value that the display apparatus supports is G MAX , and the N grayscale combinations comprises (0, 0, 1), (0, 0, 2) . . . (0, 0,G MAX ), (0, 1, 0), (0, 2, 0) . . . (0, G MAX , 0), (1, 0, 0), (2, 0, 0) . . . (G MAX ,0,0) and (0, 0, 0),
wherein one of the M grayscale combinations is (R 0 ,G 0 ,B 0 ), the blended result is (X′,Y′,Z′), and the set of color blending equations comprises:
X′=X ( R 0 ,0,0)+ X (0, G 0 ,0)+ X (0,0, B 0 )
Y′=Y ( R 0 ,0,0)+ Y (0, G 0 ,0)+ Y (0,0, B 0 )
Z′=Z ( R 0 ,0,0)+ Z (0, G 0 ,0)+ Z (0,0, B 0 )
wherein, X(R 0 ,0,0), Y(R 0 ,0,0) and Z(R 0 ,0,0) represent the color performances of a grayscale combination (R 0 ,0,0) in a CIE XYZ color space; X(0,G 0 ,0), Y(0,G 0 ,0) and Z(0,G 0 ,0) represent the color performances of a grayscale combination (0, G 0 ,0) in the CIE XYZ color space; and X(0,0,B 0 ), Y(0,0,B 0 ) and Z(0,0,B 0 ) represent the color performances of a grayscale (0,0,B 0 ) in the CIE XYZ color space.
8. The method according to claim 7 , wherein a maximum grayscale value that the display apparatus supports is G MAX , and the N grayscale combinations comprises (0, 0, 1), (0, 0, 2) . . . (0, 0, G MAX ), (0, 1, 0), (0, 2, 0) . . . (0, G MAX , 0), (1, 0, 0), (2, 0, 0) . . . (G MAX , 0, 0), (0, 0, 0), (1, 1, 1) . . . (G MAX , G MAX , G MAX ).