Abstract: A method provides for an improved chroma-key suppression technique. The improved method reduces a halo-like effect which might otherwise appear in a composite image containing a foreground object selected from a first image and a background image selected from a second image. In accordance with the present invention, a chroma-key patch is translated into x, y axis coordinates and one or more pixels of the image in question can be compared to a chroma-key patch and a transition region at least partially surrounding the chroma-key patch to better select suppression signals to be applied in an image processing operation.

Abstract: A system and method for coding colors and storing compensation factors used in converting colors from one color space to another color space. A color is converted from a first color space to a second color space using a color space converter. If one or more components of the second color is invalid in the second color space, a constant hue algorithm is used to create a compensated color which is valid in the second colors space. Specifically, a compensation determinator determines a compensation factor which is used in a compensation adjuster along with a constant hue algorithm to create the compensated color triplet. As a result of the constant hue algorithm, one of the color components of the compensated triplet is either zero or saturated. All except two bits of the storage space for the zero or saturated compensated color component are used to store the compensation factor.

Abstract: A method and system for recording an asynchronous, biphase encoded signal (such as a MIL-STD-1553B signal), having a first data rate, on a video tape recorder, which may be a consumer video tape recorder, and for recovering the encoded recorded data for subsequent transmission in its original format. The asynchronous biphase enceded signal is synchronized with a clock signal having frequency equal to twice the first data rate. The synchronized signal is then stored temporarily in a buffer memory as if it were an NRZ bit stream having bit rate equal to twice the first data rate. The data is read out of memory and combined with television-type synchronization pulses to produce a television-type signal for recording on the VTR. In the play back mode, the recorded VTR signal is separated into its data component (which consists of bursts of data that occupied the active video areas) and sync component. The invention eliminates the need to use specially designed recorders for asynchronous biphase encoded signals.

Abstract: An encryption system in which a code word is processed, byte by byte, by a Vernan type process followed by non-linear encryption techniques, all of which are repeated several times, to generate a working key schedule. This key schedule is then used in the same process to encrypt the text.

Abstract: An 8/9 encoding scheme wherein the improvement comprises selectively outputting, in response to a sync control signal, a first and a second 9 bit code word that uniquely identify a synchronization point in the 9 bit data word stream. The first code word is 1 1111 1111.sub.2 (1FF.sub.16) if the digital sum variation (DVS) is less than zero and 0 0000 0000.sub.2 (000.sub.16) if the digital sum variation is greater than or equal to zero. The second code word is any .+-.1 CDS entry of the same CDS polarity as the first word. In a preferred embodiment of the invention, the second code word is 1 0101 0101.sub.2 or 155.sub.16 (CDS=+1) or 0 1010 1010.sub.2 or 0AA.sub.16 (CDS=-1).

Abstract: A method of updating an optical memory disc, the disc being of the type that has a plurality of zones, one of the zones containing at least one directory block that includes a plurality of entries in the form of addresses which point at data. The method comprising the steps of reading the entries of the one directory block into a temporary location; altering the entries of the one directory block with new directory information; dividing the entries of the one directory block into two new directory blocks, each of the new directory blocks being designated by a separate pointer; writing the two new directory blocks from the temporary location onto the optical memory disc; and storing the pointers in a new directory pointer block of the optical memory disc, whereby subsequent addition of new directory information requires the alteration of less than all of the directory blocks.

Abstract: A system and method for simulating the operation of a video disk player playing an interactive video disk, which comprises a video tape player, a timing code reader, a monitor, a computer, and an input device. A control program is entered into the computer through the input device. A video tape is loaded in the video tape player. The video tape player generates video signals and a timing code signal associated therewith. The video signals are displayed on the monitor. The timing code signal is converted into an output signal by the timing code reader. The computer, under operator control, controls the operation of the video tape player, in response to the output signal and the control program such that the video signals displayed on the monitor simulate the operation of a video disk player playing an interactive video disk.

Abstract: A controller for a video tape recorder (VTR) which allows a plurality of separate tape times to be cued at the selection of the operator by means of separate cue registers and corresponding cue switches operating in conjunction with a programmed controller and a tape time counter which is slaved to the VTR tape timer. The controller also causes the VTR to search for cued tape times as stored in selected ones of the cue registers and, at the option of the operator, to stop the tape at a tape time slightly prior to a selected one of the cued tape times. Digital, fine and coarse clock tape time displays are also provided for indicating the tape time, when the tape is moving, and selected cued tape times when the tape is stopped.