Abstract: Video effects apparatus comprises a pattern generator for generating a mix control signal which, when used to control the combination of first and second input video signals to provide an output video signal, defines the geometrical shape in a composite output scene of a transition between a first component scene represented by the first input video signal and a second component scene represented by the second video signal. The pattern generator responds to a size control signal by causing the mix control signal to vary in a manner such that the area of the composite output video scene that is occupied by the first component scene changes relative to the area of the second component scene while the geometrical shape of the transition between the component scenes remains the same. A shadow generator generates a signal which adjusts the visual characteristics of the second component scene synchronously with the variation of the control signal.

Abstract: A Simple Code encoder/decoder converts a ternary, or bipolar, signal having a strong clock component into a binary signal while maintaining the strong clock component for processing with digital equipment. The Simple Code is high for each positive value of the bipolar signal, low for each negative value of the bipolar signal, and alternates high/low for each zero value of the bipolar signal. The encoder uses an extractor circuit to generate a +PULSE signal, a -PULSE signal and a CLOCK signal from the bipolar signal. The +PULSE and CLOCK signals are combined to produce an intermediate binary signal, and the intermediate binary signal is combined with the -PULSE signal to produce the Simple Code binary signal. The decoder extracts the CLOCK signal from the Simple Code binary signal and uses the CLOCK signal to generate positive and negative pulse signals corresponding to the highs and lows of the binary signal of a duration equal to the period of the CLOCK signal.

Abstract: An audio mixer architecture using virtual gain and switching has a single gain stag in each audio input signal path. A plurality of audio input signals are input to respective audio input channels having two or more active gain elements at the output to provide parallel signal paths for each audio input signal. The audio signals from the active gain elements are combined to form up to four audio output channels in any desired combination of audio input signals. The individual audio input signal gains and the master audio output signal gains are synthesized together as a single gain control signal for each active gain element to simulate successive gain stages for each audio input signal path within a single gain stage for that path.

Abstract: A video signal representing a scene is processed by combining it with a second signal having a value which depends on the depth of the scene as a function of position.

Abstract: A digital video effects apparatus comprises an input for receiving a digital input video signal representing the distribution of optical information over a video field, and a key signal generator for providing a digital key signal that defines an area of the video field. A mask signal generator provides a digital mask signal that defines at least a portion of said area of the video field. The digital mask signal is combined with the digital key signal to provide a modified digital key signal, and the input video signal is acted on in accordance with the modified key signal to provide an output video signal.

Abstract: An optical device compensator obtains from an input modulating signal an additive component and a multiplicative component. The additive and multiplicative components are combined with the input modulating signal to produce a compensated modulating signal which is applied to a driver for modulating an optical device.

Abstract: A video discriminator for automatically providing a format select indicator generates from the number of vertical sync pulses in a vertical interval of an input video signal and from the current state of the format select indicator an error signal if the number of vertical sync pulses is incompatible with the format select indicator. The error signal and a vertical sync detect pulse together with a horizontal line count determine the format of the input video signal and cause the format select indicator to change to reflect the format of the input video signal.

Abstract: An apparatus for smoothing an abrupt change in signal level generates a control signal having a curvilinear ramp shape. An amplifier has a step input signal applied to a non-inverting input, a delayed slope control signal applied to a bias terminal, and the output of the amplifier fed back to an inverting input. An RC series circuit is connected between the output of the amplifier and a reference potential, with the control signal taken from the node between the resistor and capacitor. The amplifier is saturated by the step input signal, and is subsequently turned on by the delayed slope control signal so that the amplifier acts initially as a current source for the RC circuit until the slope control signal reaches its full value. Then the RC circuit charges linearly until the intercept voltage of the step input is approached, at which point the amplifier comes out of saturation and acts as a voltage source to exponentially charge the capacitor to the intercept voltage.

Abstract: A video switcher comprises a source selector having a plurality of input terminals for connection to a plurality of video sources respectively, and at least two output terminals. At least two processing channels each have an input terminal connected to an output terminal of the source selector and also have an output terminal. A video combiner has video input terminals connected to the output terminals of the processing channels and is operative to combine the output signals provided by the processing channels in dependence upon priority signals.

Abstract: A digital data rate compression system accepts an input digital signal having a plurality of samples at a given rate and outputs a digital signal at one-half of the given rate, or as an expansion system outputs a digital signal at twice the given rate. The digital data rate reduction technique uses multi-rate digital filtering in the form of a half bandwidth filter. In the case of the digital filter the input digital signal is separated into even and odd samples which are input to separate delay lines at one-half the given rate. The even samples are summed in pairs symmetrically about the center of the even delay line, and each pair is weighted according to a modified sin(x)/x function with simple coefficients which may be accomplished by additions and shifts, to eliminate the need for multipliers.

Abstract: A first shaped video signal V.sub.1 K.sub.1 and a second shaped video signal V.sub.2 V.sub.2, are combined so as to generate a third shaped video signal V.sub.3 ' given byV.sub.3 '=V.sub.1 K.sub.1 [1-K.sub.2 (1-P.sub.12)]+V.sub.2 K.sub.2 (1-K.sub.1 P.sub.12)where P.sub.12 is a priority signal. A key signal K.sub.3 given byK.sub.3 =1-(1-K.sub.1)(1-K.sub.2)is also generated. An output processor receives the shaped video signal V.sub.3 ', the key signal K.sub.3 and a matte signal M.sub.3. In a first mode of operation, the output video signal V.sub.3 " of the output processor is given byV.sub.3 "=V.sub.3 +M.sub.3 (1-K.sub.3)and the key signal K.sub.3 ' that is generated by the output processor has a constant value, and in a second mode of operation of the output processor the output video signal is given byV.sub.3 "=V.sub.3 '/K.sub.3and the key signal K.sub.3 ' is directly proportional to K.sub.3.

Abstract: Electrical apparatus comprises a backplane board of dielectric material and at least one run of conductive material. An aperture extends through the dielectric material and through the run of conductive material. A conductor member may be connected to the run of conductive material by means of a connector comprising a first connector member secured to the conductor member and a second connector member that is mechanically mateable with the first connector member. One of the connector members has an essentially rigid elongate member of conductive material that is embedded in a block of dielectric material and can be inserted into the aperture from one side of the board to contact the run of conductive material and that, when so inserted, projects from the other side of the board. The block of dielectric material prevents inadvertent contact with the live electrical conductors of the backplane.

Abstract: A circuit for extracting phase averaged horizontal timing with high noise immunity and for rapidly acquiring a video signal from a composite synchronizing signal generates an output signal at the horizontal sync rate, the output signal having leading edges occurring at the leading edges of the horizontal sync pulses of the composite synchronizing signal. The rate of the output signal is phase averaged by comparing the respective leading edges of the output signal and the composite synchronizing signal within a window centered about the leading edges of the output signal. Difference in the phases of the respective leading edges result in an error signal which is used to adjust the rate of the output signal to obtain coincidence of the respective leading edges. The occurrence of the leading edges of the composite synchronizing signal within the window is used to lock the circuit.

Abstract: A transition status display for a video switcher inserts a single, readable synopsis of a next transition event into a video output signal from the video switcher for display on a monitor. The synopsis is in the form of a window having a line segment representing a time line between a prior transition event and the next transition event, the type of the next transition event being indicated graphically. Various tic marks represent significant events in time from an initial tic mark representing the time of the prior transition through a final tic mark representing completion of the next transition. Appropriate alpha-numeric characters are provided with the line segment to label the significant events, to identify the current and next video sources, and to provide time information, the time information being constantly updated together with an analog marker which moves along the line segment as time progresses toward the next transition.

Abstract: A method of processing a foreground array of sample values, a background array of sample values and a crop array of sample values, which three arrays are coextensive and wherein the crop array represents a geometrical figure associated with a non-zero multiplication factor surrounded by a marginal area associated with a zero multiplication factor, comprises selecting a low-pass filtering operation to be carried out on the foreground array, and modifying the crop array so that when the selected low-pass filtering operation is carried out on the modified crop array, the sample values at the periphery of the domain of the resulting filtered crop array are all associated with a zero multiplication factor. The selected low-pass filtering operation is carried out on the foreground array and the modified crop array to provide a filtered foreground array and a filtered crop array respectively. The background array and the filtered foreground array are combined under control of the filtered crop array.

Abstract: A centering sleeve for minimizing angular displacement of an electrical connector within a connector block has an internal hole adapted to fit closely onto the electrical connector and an external surface adapted to fit snugly within a hole in the connector block into which the electrical connector is to be inserted. The centering sleeve may have a longitudinal slit to allow the centering sleeve to be installed after the electrical connector is already attached to a coaxial cable, and depending upon the thickness of the wall of the centering sleeve may have an internal notch parallel with and diametrically opposed to the slit to provide an integrated hinge to facilitate installing the centering sleeve.

Abstract: Video effects apparatus comprises a wipe generator for generating a wipe signal and a matte generator for generating a matte signal. The matte generator receives the wipe signal and the color represented by the matte signal is dependent on the wipe signal. First and second control signals are provided in response to the wipe signal. A first video mixer has signal input terminals connected to receive a first video signal and the matte signal respectively and a mix control input terminal connected to receive the first control signal as a mix control signal, and a second video mixer has signal input terminals connected to receive respectively a second video signal and the output signal of the first video mixer. The second mixer has a mix control input terminal connected to receive the second control signal as a mix control signal.

Abstract: A diagnostic system for a digital signal processor, having an input module, an output module and a plurality of successive processing modules defining a signal processing path, monitors various internal test points within each module. Any one of the test points may be connected to a diagnostic bus. The output of the diagnostic bus may be appropriately modified and input to the output module in lieu of the digital signal from the last processing module to provide a diagnostic display.

Abstract: Video special effects apparatus comprises both an analog pattern generator and a digital pattern generator. The analog control signal generated by the analog pattern generator and the digital control signal generated by the digital pattern generator are combined to provide a hybrid control signal, and the hybrid control signal is used to control the wipe between two video signals.

Abstract: A numerical precorrection technique for modifying a digital signal corresponding to a desired analog signal to compensate for the characteristics of an analog filter which processes the digital signal after it is converted from digital to analog converts the digital signal into its spectral components. The spectral components are corrected according to the corresponding spectral characteristics of the analog filter for both amplitude and phase within the filter pass band and for phase only outside the filter pass band. The resulting corrected spectral components are converted into a corrected digital signal which is used to produce the desired analog signal.