Abstract: A method and device make it possible to show information interactively on a user terminal of an image display system, without requiring additional bandwidth for transmitting feedback information. The image display system includes an image source device and a user terminal connected to each other via a link. An input image signal and user command are received and, based on these, a further image signal representing an image part is generated. A compressed image signal is formed from the input image signal and an imposed image part. The compressed image signal is transmitted to the user terminal via the link where decompression occurs.

Abstract: Users control the movement of avatars through a virtual space. The system keeps track of the location of the avatars and forms a picture of the virtual space for each user. Users can select themselves to act as a cameraman. The picture of the virtual space around the location of the avatar is then transmitted separately to passive viewers via a broadcast channel. Conversation between the cameraman and other users is broadcast also via the broadcast channel. The picture broadcast has a visual detail which is finer than that of the pictures received by the various users individually; movements are reproduced therein in interpolated form and are adapted in such a manner that the avatars in the broadcast signal arrive at landmarks, in time.

Abstract: The invention relates to the graphic reproduction of symbols on an imaging surface. These symbols can be controlled as regards position and/or scale. They are reproduced as successions of brightness values arranged in image lines. As a result of the use of brightness values between levels occurring in an ideal brightness profile of the symbol (for example, only black and white), high-resolution details are reproduced. In accordance with the invention, boundaries between successive image lines are used to reproduce transitions between the brightness levels as sharply as possible.

Abstract: A multiprocessor system for forming a color picture from object elements defined in a hierarchic data structure. The object elements are Bezier polygons each of the sides of which forms a Bezier curve. There is provided an array of parallel connected point processors which perform three functions. First of all, from the highest level of the data structure they determine the relevance of each object element to a point in question until either irrelevance is detected or one or more elementary object elements remain. Furthermore, for each point and each relevant elementary object element a binary inside/outside determination is made. Finally, the color is implemented by a priority determination of the elementary object elements determined to be "inside". The inside/outside decision is made in that during successive steps the relevant polygon sides are divided and in that the contribution to the inside/outside determination by the parallelogram diagonalized by the current side portion is decided.