A transmission apparatus for video information is disclosed. The apparatus has an input part for inputting video; a level information generation part for generating level information of each pixel on a screen; a memory part for storing the level information of each pixel in the entire region of the screen; a region extraction part for extracting a changed region which is a region on the screen including pixels related to the video information; an update region level information generation part for generating level information of each pixel in the changed region; a compression part for compressing the information amount of level information of each pixel in the changed region; and a communication part for transmitting position information of the changed region and the compressed level information.