A dithering method includes: utilizing a plurality of large dithering masks to perform dithering on a first set of Least Significant Bits (LSBs) of M-bit video data, utilizing a plurality of small dithering masks to perform dithering on a second set of LSBs of the M-bit video data, and adjusting the content of at least one of the plurality of large dithering masks and/or the content of at least one of the plurality of small dithering masks on a frame-by-frame basis. Each of the plurality of large dithering masks includes a plurality of sub-dithering masks. Each of the plurality of sub-dithering masks includes a plurality of dithering thresholds. Each of the plurality of small dithering masks includes a plurality of dithering thresholds.