Abstract: A time base corrector including a frame memory and a memory control. The memory control is microprocessor based and calculates the starting addresses of memory areas at which video data will be written to or read from the frame memory and the starting times of those sequences. The memory control receives information concerning the configuration of the time base corrector, the input video field sequence, the desired output video field sequence, timing components of the input and reference clock signals, TV standard, and operator commands to make these calculations. The results of the control are time base corrections for horizontal and vertical phase errors, horizontal and vertical positioning control, color frame sequencing, color correction of chroma phase, configuration delay adjustment, and other advantageous operations.

Abstract: Transmission of one or more electrical signals from a rotatable to a stationary member is provided along one or more channels, with an array of optical emitters positioned in a circle concentric with the axis of rotation of the rotatable member. A concentric array of facing optical detectors on the stationary member is coaxially spaced from the emitters. As the rotatable member is rotated, the optical detectors are sequentially switched in sync with the corresponding rotation of the respective emitter which is transmitting the signal. The direction of transmission may be reversed by reversing the location of the emitters and detectors to the stationary and rotatable members, respectively. In an alternate configuration, a concentric cylindrical embodiment with a cylindrical surface having emitters or detectors thereon rotates within a concentric stationary cylindrical surface having a circular configuration of facing detectors or emitters, respectively, thereon.

Abstract: A color field 1 detector includes analog and digital processor sections, wherein the analog processor section receives a video signal input and provides the digital signals necessary to drive the digital processor section. A timing generator receives a free-running reference clock and supplies an internal reference signal of subcarrier frequency starting at the falling edge of composite sync. A burst phase comparator compares the incoming color burst phase to the internal reference signal phase and generates logic signals indicative of the phase relationships therebetween to thus indicate whether the color burst is in phase, 180.degree. out of phase, or if any phase error exists. A state machine receives the logic signals and detects the sequence of occurrence of the states of the color burst relative to the internal reference signal. The sequence is indicative of the subcarrier-to-composite sync phase of the video signal input for the particular color television standard.

Abstract: A technique for concealing large data losses such as the 50% data loss experienced when a data channel of, for example, a two channel composite SECAM digital video apparatus is lost. The digitized video samples are grouped and the groups are distributed into alternate channels of the two digital channels. Upon receiving the data, a channel multiplexer reassembles the groups of samples. If a data channel is lost, the sample distribution pattern cooperates with selected algorithms in a compromise which allows the system to recover sufficient luminance and chrominance information to provide acceptable concealment of the lost data.

Abstract: At the input to a video signal time base corrector, the phase error is sampled during each burst interval and is used to control the operation of an analog-to-digital convertor to compensate for phase errors at the start of each line. Progressive phase errors are predicted during each line and compensated. Any residual phase error at the start of a line is detected and applied to a phase error compensator for eliminating the residual phase error. The residual phase error and the video signal are processed through separate signal paths, and the frequency and phase characteristics of the residual phase error path are adjusted to those of the video signal path.

Abstract: A carriage mechanism operable with a picker assembly mounted at the face of a bin structure having discrete bin locations within that structure for storing cassettes, the picker assembly moveable along the face of the bin structure and between bin locations, the carriage mechanism operable to extract a cassette from a first bin location, and load it into a cassette-receiving envelope of the carriage mechanism at a selected stored position of the envelope for transport to a second bin location remote from the first location. A bumper element mounted on the carriage mechanism at a fixed reference point is provided to move cassettes out of interferring relation with the carriage mechanism, by sweeping all X-Y coordinates of the face of the bin structure with the picker assembly to displace misaligned cassettes.

Abstract: A multi-standard color field sequence detector includes an analog and a digital processor section, wherein the analog processor section receives a reference video input and provides the signals necessary to drive the digital processor section. A correlator control circuit counts an exact number of 13.5 MHz reference clock cycles, and then supplies a start signal to a burst correlator circuit, which takes samples of a plurality of cycles of burst and correlates the results to determine the polarity of the burst samples. If they are of a first polarity, a count value of corresponding polarity is supplied. If they are of the opposite polarity, a count value of the corresponding opposite polarity is supplied. The sequence of the polarities of the final counts are detected to identify the color field 1 for the standard being used.

Abstract: A dynamic head position tracking control for a magnetic tape playback system employs a detected dither signal to determine the elevational position of a pair of magnetic transducing heads relative to tracks of recorded information being scanned by the heads. This detection is carried out at several locations along the lengths of the tracks being scanned, and a value is stored for each of the locations. Based upon the stored information, an estimation is made of a position value for the first location along the length of the tracks. This estimation is determined from a weighted extrapolation of the following two samples taken during the scan of the track. The elevational position of the heads is then dynamically controlled in accordance with the actual and estimated head position values.

Abstract: A technique for recovering helical audio using the standard synchronous reference clock of the video tape recorder system to conventionally clock the transport and the video signal processor, including the video timebase corrector. A modified audio signal processor clock is generated which is varied commensurate with the desired rate of tape speed override, varying accordingly the flow of audio data through an audio timebase recorder. The speed of a helical scanner is varied in accordance with the rate of tape speed override, to lock the scanner angular position to the audio timebase corrector. In turn, a capstan servo adjusts the tape position in respsonse to the scanner angular position to lock the tape to the scanner. Meanwhile, the video signal processing proceeds conventionally by skipping or repeating fields or frames via a frame store to match the rate of tape speed override.

Abstract: A method and system for encoding color frame polarity information into composite sync signals. Also, a method and system for detecting color frame polarity information which has been encoded into composite sync signals and for restoring the encoded composite sync into its normal non-encoded form.

Abstract: An animation recording process is particularly adapted to videotape recorders of the type having a control panel display, multifunction soft keys, and are microprocessor controlled. Rapid recording of large pluralities of still images is effected using the animation "cel" recording concept wherein a selected cel is recorded as a selectable repetition of a single still image is recorded without interruption between frames or fields of the cel, i.e., without recueing the transport. Using the cel concept further allows the determination of not only the subsequent cel edit entry point, but also of the subsequent cel edit exit point, whereby pre-programming the points allows automating the recording of an animated program with a minimum of operator attention.

Abstract: To position a cue location on a video tape to a scanner so that the information stored at the cue location can read by a transducer. The video tape is transported so that when the cue location arrives at the scanner, the tape is moving at a selectable desired velocity. A synchronous cueing function is also provided for, in which the cue location is advanced at the rate of the desired velocity during to cueing operation to allow the positioning to be synchronized with other devices when the cue operation is completed.

Abstract: Apparatus and method for detecting a sync signal in parallel data which has been reconstituted from serial data. The first occurrence of digital bits which corresponds to a predefined sync signal is recognized and causes the circuitry to shift to a mode of operation in which subsequent sync signals will be recognized if and only if they occur within a predetermined "window" around the expected position of the sync signal. The sync signal is used re-align the parallel data so that the bits are grouped into meaningful words.

Abstract: Tracking of a standard or non-standard input video signal, such as a NTSC or PAL composite video signal, is provided by supplying the phase difference between a horizontally-related subcarrier signal, and a variable horizontal sync signal, which is indicative of the SCH phase shift in the input video signal. The phase difference is used to generate a corresponding servo voltage, which then is used to steer the bias of a monostable and thus vary accordingly the trailing edge of a pulse generated thereby, to remove the phase difference. Thus the variable horizontal sync signal is made to coincide with the subcarrier signal, which forces the system to track the subcarrier-to-horizontal sync phase of the input video signal.

Abstract: A tether apparatus is secured at either end to suitable supports and thus spans one edge of a preselected area within which an animal is to be confined. The apparatus includes a folded back floating loop configuration, which floating loop translatably receives therethrough the end of the rope which is secured to the animal. The configuration allows the tether apparatus to collapse to allow the animal optimum freedom of movement while still providing the desired restraint.

Abstract: An electronic still store system stores and selectively outputs video image data defining a plurality of signal frame still images. The simultaneous display of up to 16 or more quarter sized images for scanning or sorting by an operator is facilitated by generating a quarter sized copy of each newly received image frame and storing both together on a conventional magnetic disk storage device as is typically employed in general purpose digital computing systems. The quarter sized image can then be recalled directly for a multi-image scan or sort function in which 16 reduced size images are displayed simultaneously without the time delays associated with the retrieval and size reduction of 16 full size images.

Abstract: A system for editing videotape includes a subsystem to scan particular information lines within vertical blanking intervals and to identify particular lines that contain time code information, and a subsystem to generate time code information and to write the generated time code information at selected lines in vertical blanking intervals.

Abstract: Tape guides of a magnetic tape transport machine are controlled during movement by sensing the position of the member as it moves along a defined path in varying velocity corresponding to the position. The member is initially accelerated at a selected rate to a maximum velocity which is then maintained until a distance close to the end position is reached. Velocity is then reduced at a selected rate until another position closer to the end position is reached. At this position a final velocity is maintained until the end is reached. A determination is made of how closely the second distance from the end coincided with reaching the final velocity. The length of the first distance from the end position is adjusted to reduce the difference between the coincidence of reaching the second distance and the final velocity. Further, the sensed final position of the member is retained as the target final position for the subsequent operation.

Abstract: A composite analog video signal is sampled at precise locations relative to the phase of the unmodulated color subcarrier along each horizontal line of the video signal. This provides a digitized signal with a constant phase relationship relative to the unmodulated subcarrier phase, which relationship may be used to remove sampling clock phase errors. The digitized samples are filtered by a digital bandpass filter to remove DC and second harmonic noise distortion. Two phase error measurements of the actual sampling clock phase are taken by averaging two sets of burst samples at 0.degree. and 180.degree. crossings, respectively, on selected horizontal lines. These phase error measurements are separately stored, and then are updated on selected alternate horizontal lines to cancel sampling nonlinearity errors. The updated signals are differenced to provide a phase error signal indicative of any sampling clock phase errors.

Abstract: Angular rotation of a member, such as the shaft of a tension arm assembly, is sensed by the combination of a circular type of magnet secured to the rotatable member and selectively polarized relative to its diameter to define a magnetic north-south pole pair, and a stationary Hall Effect transducing device secured in close and constant proximity to the ring magnet. A circuit coupled to the transducing device includes offset and amplification stages. In a preferred embodiment, the Hall Effect transducing device is located in the region of a magnetic null of the field generated by the magnetic poles, when the rotatable member is in a selected angular position. The constant gap between the transducing device and the circular magnet optimizes the generation of a linear output via the circuit, to accurately sense the member rotation.