Digital television channel medium for interactive programs, projects marker onto object in synchronized image and sound channel stream

摘要

The medium is a data application comprising a marker which is projected into an image plane in a receiver for transmission and used to mark at least one predetermined object in at least one image and sound channel stream. The marker is guided in the image plane using a pointer device, preferably a television remote control, which is adapted to interact with the data application. The position of the object in the image channel stream is input into the application for each actual image frame in this stream. A first synchronization between the application and image channel stream is generated by the application reading code in this stream whenever this code is available, so that the application can be positioned in this stream. A second synchronization at image frame level is carried out by using a clock for the channel medium to interpolate the position of each frame between two available codes, allowing the position of the object in the application and in relation to the frames in the image channel stream to be synchronized using the code and interpolation, which enables the marker to be used to mark the object in the image and sound channel stream and interact with the interactive program according to set marking rules present in the program. A predetermined continuous transmission of the application in a data channel stream and the image and sound channel stream is performed, the application being activated to broadcast in the image plane by detecting a predetermined code in the image stream in sufficient time in advance of the transmission of an interactive program, so that the application is generated by the program at the program starting time using the two synchronizations. An independent claim is included for a signal for generating a digital channel medium which carries the data channel stream and image and sound channel stream described above. The medium is cable television, wireless technology, CD, DVD, cassette tape or the internet.