Abstract: A method and apparatus is disclosed which minimizes the visual artifacts normally generated when images are compressed for transfer through very narrow band channels such as, for example, the Internet. To this end, the images are pre-filtered and then scaled down prior to compression using a two dimensional spatial impulse filter with good pulse fidelity rather than flat pass bands, rapid cutoff at high frequency and minimal impulse response width. The impulse filter preferably is operated at the 6 db point down about 0.6 to 0.9 of the output image spatial band edge, thereby removing visible aliases in the images while compromising between subjective sharpness and total picture entropy.
Abstract: An easily installed inter-row transfer unit is disclosed employing a movable cartridge bin assembly suspended via linkage from a pair of bearing blocks, wherein the resulting bin assembly carriage travels horizontally along a support housing extending between front-to-back arrangements of rows of library systems, to enable expansion of the library systems into very large mass storage systems. The pair of bearing blocks of the bin assembly carriage are spread or closed to respectively raise or lower the bin assembly from or into a respective library system. Thus, vertical as well as horizontal motions of the bearing blocks are controlled by a motor/cable drum drive device secured to the support housing. In a preferred embodiment, a trapdoor mechanism and a cooperating roller support mechanism are used to enable reversing the direction of horizontal translation of the bin assembly carriage with a single motor/cable drum drive device. Various other embodiments and modifications are illustrated.
Abstract: The present application discloses an electronic switching device in combination with a low noise, low input impedance preamplifier circuit. The resulting electronic preamp assembly is specifically configured so that it can be directly interchanged with existing mechanical relay/preamplifier assemblies such as those presently in use in recorder/reproducer apparatus having dual function record/playback heads, without disturbing the associated operating parameters of the record or playback channels. The electronic preamp assembly includes a balun transformer and a solid state switch coupled from a record amplifier to the record/playback head via a rotary transformer to define the record channel. The playback channel includes a diode bridge switch and a preamp circuit also coupled to the rotary transformer and head.
Abstract: A read/write magnetic head includes a step offset formed in the gap of the head which accordingly generates recorded transitions in a recording medium which also contain a step offset in each successively recorded transition along the length of a track. On subsequent playback of the track by the same or similar step gap head, fine transverse mistracking of the head as it follows the track results in a corresponding echo signal being generated along with the main readout signal. The amplitude of the echo signal is indicative of the degree of fine mistracking while the location of the echo signal relative to the main signal is indicative of the direction of mistracking. Fine mistracking correction is provided by circuits which detect the amount and direction of mistracking and supply an error signal to a tracking servo to correct the mistracking.
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 improved magnetic head structure which places a laminate at the gaps of the head, said laminate deposited on each substrate facing the gap, and comprising alternating layers of first and second magnetic materials, said first material having a higher coercivity than said second material.
Abstract: A method and apparatus for controlling the capstan servo of a magnetic video tape recording and reproducing machine is disclosed. The invention provides almost instantaneous color framing and synchronous control track lock when accelerating from a very slow tape velocity up to normal velocity. An embodiment of the apparatus also stops the tape at a predetermined position relative to control track transitions when stopping the machine from a noncontrol track lock operating mode, such as shuttle, variable velocity reproducing and jog.
Abstract: A bar code reader system includes a stream of pulses whose period is a function of the scan speed of the reader as it scans the bars and spaces of a bar code symbol. Transition pulses are supplied which identify the boundaries of the bars and spaces. The tach pulses which occur between transition pulses are counted, loaded into memory, and are read from memory via microprocessor means, whereby the widths of the bars and spaces are determined. The sequence of the bar and space data is decoded to yield the bar code encoded numbers.
Abstract: A coding array usable on a series of cassettes of varying size, the array symmetrically located in a threading area of the cassette with respect to designated cassette reference points, to present the array of each size cassette to the associated recorder at the same relative position, each array incorporating a record inhibit device for the cassette.
Abstract: To stabilize the transducing head of a magnetic disc memory apparatus, the head is mounted on a flexible leaf aligned transverse to the disc radius; the upstream leaf end is fixed to the head carriage, and the downstream leaf end is restrained against motion normal to the disc surface. The head is secured at a point on the leaf where the tangent to the leaf is always parallel to the disc surface; the head may be balanced on both sides of the leaf; and the leaf may be formed of two parallel members with torsional vibration damping material therebetween.
Abstract: A method and system are provided for generating a synchronized handshake between communicating parts of a digital system operating from a common clock. A request signal is sent from an initiating station to a responding station. The responding station acknowledges receipt of the request by sending an acknowledge signal back to the initiating station, thereby completing a so-called handshake. In accordance with the invention both the request and acknowledge signal are pulses of a fixed duration greater than one but less than two clock cycles. A new request signal may be transmitted concurrently with the reception of an acknowledge signal, resulting in a maximum handshake rate of one half of the common clock rate.
Abstract: A frequency measuring circuit measures the period between successive pulses of an input signal and converts the pulse count to a measured frequency value. The measured frequency signal is filtered to eliminate spurious noise and a variable threshold is generated by comparing the measured frequency and the filtered frequency. Only frequency signals qualified by the variable threshold are accepted as valid and provided as the output.
Abstract: A method and system for composite system phase control in a signal processor such as a television video recorder operating in a genlocked system. A synchronizing signal, preferably a frame-rate horizontal reset pulse, is generated in response to coincidence between predetermined parts of two timing reference signals, in particular color television frame-rate horizontal line reference pulses and clock pulses derived from the color subcarrier. Possible coincidence ambiguity between the two timing reference signals exists when transitions in the two signals occur within a predetermined time period. The phase of one of the reference signals, the subcarrier frequency clock, is shifted 180 degrees (one-half cycle) to eliminate the potential coincidence ambiguity.
Abstract: Information related to the beginning of data and the phase of color burst on consecutive horizontal scan lines of a digital color television signal is encoded into a variable width pulse. A first transition of that pulse has a predetermined phase relationship with the beginning of data on each line. A second transition of the variable width pulse is formed by providing a delayed transition with respect to the first transition in a variable delay circuit. The second transition is delayed by different amounts of delay, each corresponding to a particular predetermined color burst phase on that particular line.
Abstract: A method and apparatus for the extraction of luminance information from an analog composite video signal. Non-luminance information in the video signal is 180.degree. out of phase between adjacent lines in adjacent fields of a video signal. Appropriately filtered adjacent fields are summed to cancel non-luminance information, leaving the desired luminance information. A field store is employed to allow the summing of adjacent fields by storing the present field to be summed with the next field of the video signal.
Abstract: A digital effects unit is integrally combined with a video switcher apparatus by interrupting various selected video signal and control paths in the switcher and, in particular, the mix effects signal from the first mixer and the pattern signal from the pattern generator, and re-routing the corresponding signals to respective inputs of the digital effects unit. The resulting manipulated video and key output signals therefrom are supplied to a second, downstream mixer which combines the digital effects with conventional switcher effects.