Abstract: A video communications system is provided that makes it possible for home viewers to download a movie in digital format from a large archive library, store the digital movie file locally, and view the movie at any convenient time. The system may limit access to particular movies and provides an accounting system that is used to bill downloads to the viewer's account as well as to post royalty payments to movie providers. Frequently viewed movies are quickly accessible via random access mass storage while infrequently viewed movies may be called up from a streaming tape archive. The digitalization of the program source allows for playback at various speeds, as well as pause, with no distortion or loss in picture quality.

Abstract: A control circuit for controlling the erasing of an information signal recorded on an optical disk such that the information signal is erased except for the vertical blanking interval and for the interval corresponding to the address signal of the information on the disk. The rest of the information signal including the horizontal synchronizing signal is erased either continuously or intermittently or is not erased. The circuit produces a control signal which assumes a first logical state for enabling the erasing and a second logical state for disabling the erasing responsive to a horizontal synchronizing signal, a vertical synchronizing signal and a command signal commanding the erasing of a particular information signal on the disk.

Abstract: A first PLL circuit receives a color burst signal of a carrier chrominance signal and outputs a first continuous wave signal which is identical in frequency and phase to the color burst signal. The first continuous wave signal is frequency converted by a first frequency divider and a second PLL circuit into a second continuous wave signal having a frequency of the sum of or difference between frequencies of the carrier chrominance signal and a derived low-frequency conversion chrominance signal. A multiplier multiplies the carrier chrominance signal by the second continuous wave signal. An output signal from the multiplier is supplied to an extraction circuit to obtain the low-frequency conversion chrominance signal.