Abstract: In a method and apparatus for transmitting information from producer to end viewers, the information is provided on a first recording medium recorded at a standard speed and in a standard format in a series of tracks slanted relative to a direction of movement of that medium. The information is reproduced from the series of tracks on the first recording medium in the form of electric signals seriatim at increased speed on the order of a multiple of the standard speed. The reproduced information is simultaneously rerecorded from the electric signals seriatim in a standard format with series of tracks on several second recording media at the increased speed, for replay of that recorded information by several end users at different times from the several recording media at standard speed.

Abstract: Method and apparatus for in-band, video broadcasting of commands to interactive devices are described. Control data are encoded by subliminally modulating, prior to the remote, composite video broadcast of video program material, a selected sequence of video image fields. The resulting modulated video fields within the viewing area of a television, each having alternately, proportionately raised and lowered luminance horizontal scan lines, are monitored by a light sensitive device positioned adjacent the user's television screen. A semirigid, twisted pair cable connects the device to nearby receiver/transmitter electronics that discriminate the binary data from the program material and amplitude modulate a high frequency infrared (IR) carrier with the data. Interactive devices, e.g.