1. An image display method performed on a display apparatus, comprising: sampling an image to be displayed, by a sampling circuit, row by row and column by column in a predefined order by using a rectangular sampling area with a size matching at least one preset characteristic pattern, wherein after obtaining an image within a sampling area, the method further comprises: comparing, by at least one processor, the image within the sampling area with each of the at least one preset characteristic pattern, respectively, to determine whether the image within the sampling area matches any of the at least one preset characteristic pattern; in a case where the image within the sampling area matches any of the at least one preset characteristic pattern, obtaining, by the at least one processor, a gray scale value for at least one monochromatic sub-pixel among multiple monochromatic sub-pixels corresponding to the sampling area in a value assignment manner corresponding to the preset characteristic pattern, and marking, by the at least one processor, the at least one monochromatic sub-pixel in a state marking matrix as gray scale value being determined and unchangeable; and in a case where the image within the sampling area does not match any of the at least one present characteristic pattern, calculating, by the at least one processor, gray scale values for multiple monochromatic sub-pixels corresponding to the sampling area according to the markings of the multiple monochromatic sub-pixels in the state marking matrix and the image within the sampling area, and marking, by the at least one processor, the monochromatic sub-pixels in the state marking matrix as gray scale value being determined and changeable or being processed but gray scale value to be determined; wherein all the markings in the state marking matrix correspond to all the monochromatic sub-pixels for displaying the image by the display apparatus, in a one to one manner, and in an initial state, all the markings in the state marking matrix, which correspond to all the monochromatic sub-pixels, are unprocessed.