Abstract: In a display device equipped with a picture-in-picture function, during controlling of the picture parameters of the main picture, one or several auxiliary pictures are presented on the screen, each having a certain combination of parameter settings. These may be preprogrammed, defined by a user, or automatically determined. The display device is provided with circuitry for transferring the parameter settings of one of the auxiliary pictures to the main picture. In a special embodiment, an auxiliary picture represents the parameter settings at the start of the picture parameter adjustment process. As a result, the old parameter settings may be compared with the new ones and, if so desired, may be reinstated in a simple manner.

Abstract: MPEG2-based transmission systems transmit a large number of digital television programs in a single physical channel. Disclosed herein is a "Channel Navigation System" which allows a user to get an overview of the digital programs provided, and to easily select a desired program. The method of the invention includes the transmission (in a separate program of a transport stream) of a video stream representing a mosaic picture, the sub-pictures of which are miniature versions of the video stream of other programs in that transport stream. The method further includes the transmission of information which links the position of each sub-picture within the mosaic picture with the program number from which the sub-picture is derived. The user selects a desired program by merely `pointing and clicking` its miniature version in the mosaic picture.