Abstract: An apparatus for modifying the appearance of the points of an image on the screen of a graphic image display console comprising a graphic memory storing all the points of the screen interposed between the screen and the display console and a control processor. The graphic memory is organized in words of n bits, each bit is representative of the state of a point of the image and has a value 1 or 0 depending on whether the point which it represents in the image is visible or merges with the background of the image. An attribute memory contains the attributes of each of the image points. The device also comprises a decoder for selecting a bit from each word read out from the graphic memory. A modification circuit is connected to the decoder, to the attribute memory and to the processor for modifying each attribute of the point corresponding to the bit selected of a word by means of modification bits supplied by the processor and for storing each modified attribute in the attribute memory.