1. A method for processing an image in a video data, the video data comprising a plurality of frames, the method comprising: obtaining a first difference set between pixel information of one of the frames and pixel information of another one of the frames, wherein the two frames involving the first difference set are one frame apart; examining a first criterion with the first difference set; and performing cross color suppressing operation on pixel information of a current frame of the plurality of frames according to a set of stationary image judgment information comprising the result of the first criterion examination.