16. A method for establishing a video database by a host, wherein the host comprises at least a processor, and wherein the processor is configured for: storing a plurality of video bitstreams into a database, wherein the database is stored in a storage device; and establishing meta-data of each of the video bitstreams, wherein each of the meta-data is established by: segmenting the video bitstream according to a scene change point to generate a plurality of shots; indexing the shots by assigning a corresponding index tag to each of the shots according to a content of the shot; and establishing a semantic pattern of each of the shots according to a video feature of the shot, wherein the meta-data at least comprises the index tags and the semantic patterns corresponding to the shots.
19. The video database establishing method according to claim 16 , wherein the shots are indexed by assigning the corresponding index tag to each of the shots by adopting a motion vector (MV) direction of the shot.