Abstract: With a digital audio or video recorder/playback decoder, an erasure flag signals (1) that an error(s) was not detected in a video signal or that an error(s) was detected and was corrected or (2) that an error(s) was detected and was not corrected. Decoders either (1) may not detect certain errors, called "unflagged errors," or (2) may detect certain errors but not correct those errors, called "flagged errors." Here, video signal data, which may have flagged or unflagged errors, is concealed. The structure detects an unflagged error in the digital data and modifies the concealment flag of that digital data. The structure also detects a first-good sample of digital data; sets the erasure flag of the first-good sample to indicate that it is to be treated as having a detected error; and extends the first-good sample to an ECC system and to a miscorrection detector.

Abstract: A keyed, true-transparency combine and keyer receive prioritized image information signals and their corresponding input key signals. On the one hand, others have changed the order of the channels carrying the image signals as the priority of the image signals changes. On the other hand, here we interchange the order of a plurality of substantially identical keyer units within a keyer as the priority of the image signals changes. In interchanging the keyer units, true transparency processed key signals are also generated. In so doing that, the i-th keyer unit modifies the value of its input key signal Bk.sub.i using values of input key signals from higher priority channels. Thereby a true transparency processed key signal Pk.sub.i is generated for the i-th priority channel. In one embodiment, a key-taken signal is generated by multiplying a key-requested signal and a key-available signal while a key-now-available signal is generated by subtracting the key-taken signal from the key-available signal.

Abstract: A method and apparatus for equalizing high frequency video signals is disclosed. A video signal to be equalized is received at an input terminal of a network and an equalized video signal is provided from an output of an operational amplifier to an output terminal of the network. The equalized video signal is fedback to one input of the operational amplifier. The video signal to be equalized is coupled to another input of the operational amplifier and is also coupled to respective ones of a plurality of alterable circuit elements such as varactor diodes, which function to mitigate distortions to the frequency response characteristic of the video signal to be equalized by cancelling the effect thereon by the video signal to be equalized.

Abstract: A symbol generator with pipeline architecture comprised of a series of processing stages that regenerate a complete video data signal for each display field. Any symbol in a display may be moved in real time and independently of any other symbol, because the display is regenerated for each and every field. The symbol generator includes a cpu microprocessor, vertical sorter, boundary generator, horizontal sorter, and color palette.

Abstract: A symbol generator that provides a video color signal that presents different colors for different portions of a symbol is illustrated herein. The symbol generator includes a number of separate stages that are connected in series to provide a processing pipeline. Elements for providing vertical color blends between the top of a symbol or selected background area and bottom of the symbol or background area are divided between the processing stages. Vertical color blending is achieved by mixing a difference color into a start color in an amount determined by the depth or displacement of consecutive raster lines from the top of the symbol.

Abstract: An apparatus and method are provided for controlling the level of an audio output signal which has been recorded and is played back from a magnetic tape at a low or zero tape speed, such as utilized in jog mode or variable speed playback during editing. A gain control signal is provided to eliminate a disturbing repetitive audio signal which accompanies stop motion playback and to reduce that signal level at low tape speed playback. The gain control signal is made dependent on the magnitude of tape speed, and it is applied to adjust the audio output gain of the playback channel.

Abstract: A video effects system having a video channel with a recirculating loop for incoming video including means for processing or cutting the video signal during each recirculation, and separately processing video information from the recirculation loop to a combiner at the data output, so that the data output video may be different from the recirculated video.

Abstract: The present invention relates to a computer-implemented technique for drawing directed graphs providing reduced crossings and improved picture quality. An edge list description provided by a user is processed to produce a ranking of all nodes that minimizes the weighted sum of all edges, an edge cost being the product of its weight and length. Nodes within a ranking are then positioned to reduce edge crossings using a heuristic based on node positions in adjacent ranks. Such heuristic uses a generalized median as a weighting function plus node transposition to avoid senseless edge crossings before proceeding to a next rank. Nodes are then positioned to minimize the weighted sum of horizontal distances among connected nodes. Spline control points are then computed for interconnected nodes, and a code sequence for a drawing is generated.

Abstract: A system, station apparatus and protocol for broadcasting messages to a plurality of stations which contemplate a primary receiver, also called a token site. The primary receiver is adapted to receive and store information messages transmitted from a source station to a broadcast group stations. The source continues to retransmit the broadcast message until it receives an acknowledgment control message from the primary receiver. In the event some receiver or receivers in the broadcast group do not receive the broadcast message, such receiver or receivers could request a retransmission of the message. The primary receiver, not the source station, would retransmit the broadcast message, thereby assuring a reliable broadcast system. The token site function can be rotated among the various receivers in the broadcast group to reduce storage costs. The possible token sites are identified in a token list to which stations may be added or from which stations may be deleted.

Abstract: In order to control the transfer of packets of information among a plurality of stations, the instant communications system, station and protocol contemplate first and second oppositely directed signal paths. At least two stations are coupled to both the first and the second signal paths. A station reads one signal from a path and writes another signal on the path. The one signal is read by an arrangement which electrically precedes the arrangement for writing the other signal. Packets are transmitted in a regular, cyclic sequence. A head station on a forward path writes a start cycle code for enabling each station to transmit one or more packets. If a station has a packet to transmit, it can read the bus field of a packet on the forward path. Responsive thereto, a logical interpretation may be made as to whether the forward path is busy or is not busy. If the path is not busy, the packet may be written on the path by overwriting any signal thereon including the busy field.

Abstract: In a robotics system, an image processor may use a moment generator in the identification of an object. Image signals may be provided by an image source such as a TV camera. Synchronizing signals may be extracted from the image signals and together with the image may be used to modify the image signals. Either modified or unmodified image signals may thereafter be processed. Further, the synchronization signals together with moment select signals may be supplied to a moment generator logic array which, in turn, is arranged to provide iterative control signals responsive to which the moment generator may iteratively and recursively generate moments in an orderly, time efficient manner. For example, in one embodiment, p-values (p=x.sup.i y.sup.j) may be iteratively and recursively generated (using stuffing) and combined (using a logic AND) with the image signals a(x,y) being processed to further generate ##EQU1## values, which F.sub.

Abstract: In order to control the transfer of packets of information among a plurality of stations, e.g., digital computers, the instant communications system, station and protocol contemplate first and second oppositely directed signal paths. At least two stations are coupled to both the first and the second signal paths. A station includes arrangements for reading (and writing) signals from (and on) each of the two paths. Signals are read from either path by an arrangement which electrically precedes the arrangement for writing signals on the path. If the station has a packet to transmit, it can overwrite a busy control field of a packet on either path. Also having read a packet signal from the path, a logical interpretation may be made within the station as to whether the path is busy or is not busy. If the path is not busy, the packet may be written on the path by overwriting any signal thereon. If the path is busy, the station may defer the writing until the path is detected as not busy e.g.

Abstract: The instant communications system and method for controlling both digital voice traffic and digital data traffic includes a communications path, a source station and a destination station. The source and destination stations are respectively adapted to be coupled to a source station home network and to a destination station home network. The source station is further adapted to transmit a signaling packet on a first transmit control channel. The signaling packet is for signaling a destination station that the source station has an information packet intended for the destination station. The destination station is adapted to detect the signaling packet on a second receive control channel. The signaling packet includes a field for identifying the source station which has the information packet intended for the destination station. In response to the signaling packet, the destination station is coupled to the source home network.

Abstract: A variation on a carrier sense multiple access/collision detection (CSMA/CD) system protocol for local area, packet, random access, broadcast networks is disclosed for effectively servicing both voice and data traffic. When the instant method is used, a mix of periodic voice traffic and aperiodic data traffic can be transmitted on a channel without the voice packets colliding. Also, an upper bound on the delay experienced by the periodic traffic can be established. In the instant method, aperiodic sources contend for a channel as in conventional CSMA/CD networks. However, unlike conventional protocols, periodic sources transmit a preempt field, responsive to which aperiodic sources terminate transmission. Also unlike conventional protocols, a periodic "time slot" may be delayed up to one packet transmission time when the network is busy transmitting aperiodic data.

Abstract: In known speech recognition systems, processors and methods, utterances are analyzed to obtain a set of reference signals. An unknown signal may be compared with the reference signals. The unknown signal may be said to be the reference signal with which it most closely corresponds as defined by some correspondence measure. Known signal recognition arrangements using multiple processor cells tend to be expensive, in part because they tend to use many processor cells.The disclosed system, processor and method contemplate an arrangement including an array of processor cells for time warping an unknown signal having m elements with respect to a reference signal having n elements or vice versa. The cells, responsive to control signals on a control diagonal, generate the correspondence measure. As the signals propagate through the array, the instant arrangement recirculates signals from cells near one (or first) periphery of the arrangement, e.g.

Abstract: With the advent of digital communications, it is common to transfer packets of information among a plurality of stations, e.g., digital computers. In order to control the transfer of the packets, various protocols have been introduced. However, the efficiency related to known multiples access digital communications system protocols tends to decrease as the digital signal rate increases. To overcome such problems, the instant communications system and protocol contemplate a communications loop having first and second oppositely directed signal paths. At least two stations are coupled to both the first and the second signal paths. A station includes an arrangement for writing a first signal on the first path and an arrangement for reading a second signal from the second path. In addition, the station includes an arrangement for reading a third signal from the first path.

Abstract: A communications path having at least two stations coupled thereto. During time intervals when no station on the path has a packet to transmit, start-of-cycle packets for timing and synchronizing the stations are routinely transmitted between respective ends of the path. When a station has a packet of information to transmit, the station monitors the path for detecting whether or not the path is busy. On the one hand, if the path is not busy, a predetermined delay is introduced before the station is permitted to transmit a packet. The delay is related to the electrical distance between the station, which has the packet to transmit, and a station, which priorly transmitted a packet including a start-of-cycle packet. Also, the delay begins when the priorly transmitted packet is received by the station.

Abstract: Known signal processors for matching signal patterns commonly compare an unknown signal with one of a set of reference signals. Various comparison techniques are known. One comparison technique for solving a parenthesization problem includes an orthogonal array of interconnected cells which are adapted for dynamic programming and for extending data and control information in a generally left-to-right direction as well as in a bottom-to-top direction. For solving a pattern matching problem, known arrangements for extending control information in a generally left-to-right or bottom-to-top direction do not appear to be satisfactory. The disclosed signal processor for matching signal patterns and for dynamically time warping an unknown input signal with a reference input signal generates a measure of the correspondence between the input signals. In generating the correspondence measure, the processor includes an arrangement for controlling all processor cells on a predetermined diagonal of the array of cells.

Abstract: In a network for routing traffic from an originating node to a terminating node, it is common to provide alternate routes in order to increase the number of route choices between the originating and terminating nodes. The Bell System toll network employs a hierarchical alternate routing arrangement wherein various nodes, or control switching points (CSPs), are rank ordered for defining a process of routing calls through the network, whereby some CSPs are prohibited from routing traffic through other CSPs. Hence, known hierarchical alternate routing arrangements tend to inhibit route choices, which tends toward longer, and hence more costly, routes. Such problems tend to arise from the limited capability of electromechanical switching equipment. But with the increasing use of electronic stored program controlled CSPs, they can be solved with our alternate routing method which allows route choices without regard to network hierarchy.

Abstract: The subject terminal includes a keyboard (20) having a plurality of keys (30-1 through 30-10), each key adapted to accommodate a respective finger of the typist, and apparatus (100, 150) responsive to the depression of one of the keys for generating and displaying a symbol upon a cathode ray tube. Also displayed on the cathode ray tube is a replica (300, 701) of the keyboard and a plurality of symbols (310-1, 510-1, 610-1, et seq) representing different functions for each of the plurality of keys. By altering (702, 703, 704, 705, 706) the label in a key location on the replica, the function associated with that key, for example, the symbol displayed responsive to its depression, may be altered. Thereby the operator need not reposition his fingers among the keys.