METHOD AND DEVICE FOR OBTAINING IMAGE SIGNALS

摘要

The present invention provides a method and a device for obtaining image signals. The method comprising steps of: measuring a luminance signal of a grayscale switching screen of a to-be-sampled grayscale; and processing the luminance signal of the grayscale switching screen of the to-be-sampled grayscale by a two-dimensional nonlinear fitting operation which is executed based on a two-dimensional least squares method. The present invention further provides the device for obtaining image signals. The present invention introduces the two-dimensional nonlinear fitting operation to the luminance signal of the grayscale switching screen of the to-be-sampled grayscale, so as to efficiently obtain luminance signals of different grayscale switching screens.

主权项

1. A method for obtaining image signals, comprising steps of:
measuring a luminance signal of a grayscale switching screen of a to-be-sampled grayscale; processing the luminance signal of the grayscale switching screen of the to-be-sampled grayscale by a two-dimensional nonlinear fitting operation to obtain a luminance signal of a full grayscale switching screen; and compensating the luminance of a luminance signal of a low grayscale switching screen in the full grayscale switching screen, wherein the grayscale of the low grayscale switching screen after switching the screen is from 0 to 48; wherein the two-dimensional nonlinear fitting operation is executed based on a two-dimensional least squares method; and the two-dimensional least squares method comprises steps of:
constructing the following bivariate polynomial function according to the luminance signal of the grayscale switching screen of the to-be-sampled grayscale:f(x,y)=∑ij=1,1p,qaijxi-1yj-1=∑i=1p∑j=1qaijxi-1yj-1 wherein ƒ(x,y) is the luminance signal of the grayscale switching screen of the to-be-sampled grayscale, x is the grayscale of the to-be-sampled grayscale before switching the screen, y is the grayscale of the to-be-sampled grayscale after switching the screen, p is a sampling number before switching the screen, q is a sampling number after switching the screen, and aij is a constant coefficient; andconstructing the following multivariate function by the two-dimensional least squares method according to the bivariate polynomial function:∑αβ=1,1p,q[aαβ∑g=1n(xgα-1ygβ-1xgi-1ygj-1)]=∑g=1nxgi-1ygj-1zg wherein z is the luminance signal of the full grayscale switching screen, and n is the number of grayscales of the full grayscale switching screen.