Image processing apparatus and image processing method

摘要

An image processing apparatus includes an image display unit and a luminance control unit. The image display unit includes pixels arranged in a matrix, each of which is formed of a first sub-pixel, a second sub-pixel, a third sub-pixel, and a fourth sub-pixel, and performs image display. The luminance control unit adjusts a ratio between a generation amount of first luminance generated by the first sub-pixel, the second sub-pixel, and the third sub-pixel and a generation amount of second luminance generated by the fourth sub-pixel. Over all input tones, the luminance control unit makes the generation amount of the second luminance lower than the generation amount of the first luminance and generates the second luminance so that a function representing a luminance value of the second luminance is continuous.

主权项

1. An image processing apparatus comprising:
an image display unit that includes pixels arranged in a matrix, each of which is formed of a first sub-pixel, a second sub-pixel, a third sub-pixel, and a fourth sub-pixel, and that performs image display; and a luminance control unit that adjusts a ratio between a generation amount of first luminance generated by the first sub-pixel, the second sub-pixel, and the third sub-pixel and a generation amount of second luminance generated by the fourth sub-pixel, wherein, over all input tones, the luminance control unit makes the generation amount of the second luminance lower than the generation amount of the first luminance and generates the second luminance so that a function representing a luminance value of the second luminance is continuous, wherein the first sub-pixel is a red sub-pixel, the second sub-pixel is a green sub-pixel, the third sub-pixel is a blue sub-pixel, and the fourth sub-pixel is a white sub-pixel, and wherein the luminance control unit adjusts a ratio between a generation amount of first white luminance generated by the red sub-pixel, the green sub-pixel, and the blue sub-pixel and a generation amount of second white luminance generated by the white sub-pixel, and over all input tones, makes the generation amount of the second white luminance lower than the generation amount of the first white luminance and generates the second white luminance so that a function representing a luminance value of the second white luminance is continuous, wherein, when an ability to represent an image with an n-bit tone is given, the luminance control unit calculates the function representing a luminance value of the second white luminance by performing a spline interpolation using formulas defined by
X=(1−t)2×Ax+2t(1−t)×Bx+t2×Cx,Y=(1−t)2×Ay+2t(1−t)×By+t2×Cy, andt=λ/(2n−1), where X is a X coordinate value, Y is a Y coordinate value, t is an input tone, (Ax, Ay), (Bx, By), and (Cx, Cy) are control points, and λ is a value of an input tone.