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Showing papers on "Interface (computing) published in 1992"


Patent
01 Apr 1992
TL;DR: In this paper, a peripheral data acquisition, monitor, and adaptive control system is disclosed in which a personal computer and one or more input/output (I/O) Bridge devices interface signals from electronically-controlled devices to the PC via the keyboard port, thus permitting data, such as measurement data, to be automatically and directly entered into application programs such that the PC can take action and control outputs based upon the measurement data.
Abstract: A peripheral data acquisition, monitor, and adaptive control system is disclosed in which a personal computer (PC) and one or more input/output (I/O) Bridge devices interface signals from electronically-controlled devices to the PC via the keyboard port, thus permitting data, such as measurement data, to be automatically and directly entered into application programs such that the PC can take action and control outputs based upon the measurement data. A software control program is also disclosed which allows the user to configure the system for orienting the user as to which devices are being controlled, reading digital and analog inputs, making decisions based upon the information using specific user-defined conditions, and setting digital outputs. The system is also adapted to interface with a wireless or AC power-line transmission media.

881 citations


Journal ArticleDOI
TL;DR: An experimental communication system for severely disabled persons that utilizes electrical responses from the brain is discussed, and the results of a preliminary evaluation are presented.

425 citations


Book
01 Jan 1992
TL;DR: An introduction to Human Memory and Interaction and User Modelling in HCI and Applied to Interactive Informal and Formal Specifications of User Interaction Task Scenarios.
Abstract: Introducing Human Computer Interaction. An introduction to Human Memory. Memory Structures. Knowledge and Representation. Expertise. Skill and Skill Acquisition. Organisation and early Attempts at Modelling Human-Computer Interaction. Interaction and User Modelling in HCI. Task Analysis and Task Modelling. Developing Interface Designs. Evaluations of Interactive systems. User Interface Design. Environments. Management System and Toolkits. Task Analysis. Knowledge Analysis of Tasks. Design. Applied to Interactive Informal and Formal Specifications of User Interaction Task Scenarios. Appendix.

228 citations


Patent
08 Jun 1992
TL;DR: In this paper, a broadcast receiver (22) for receiving television broadcast signals carrying encoded data e.g. teletext information, includes a tuner (30), a demodulator (32) and a data extractor (36) for decoding the data.
Abstract: A broadcast receiver (22) for receiving television broadcast signals carrying encoded data e.g. teletext information, includes a tuner (30), a demodulator (32) and a data extractor (36) for decoding the data. The receiver is coupled to a computer through a bus (38) and an interface controller (40). The tuner (30), the demodulator (32) and the data extractor (36) are each individually controllable by the interface controller (40) in response to instructions from the computer to vary any of the tuning, the demodulation parameters, or the data extraction parameters. A data processor (54) processes the extracted data, and can also control the tuner (30), the demodulator (32) and the data extractor (36).

217 citations


Proceedings Article
30 Nov 1992
TL;DR: An alternative output method for silicon auditory models, suitable for direct interface to digital computers, is described, and an integrated circuit model of temporal adaptation in the auditory nerve that functions as a peripheral to a workstation running Unix is described.
Abstract: Several research groups are implementing analog integrated circuit models of biological auditory processing. The outputs of these circuit models have taken several forms, including video format for monitor display, simple scanned output for oscilloscope display and parallel analog outputs suitable for data-acquisition systems. In this paper, we describe an alternative output method for silicon auditory models, suitable for direct interface to digital computers.

214 citations


Patent
12 Nov 1992
TL;DR: In this article, an apparatus for detecting potentially fraudulent telecommunication activity, comprising a digital computer; interface, operatively connected to the digital computer, for receiving a call information record for each call involving a particular subscriber; comparator operating within the digital computers, for comparing a parameter of the particular user's current usage with a subscriber-specific pattern of the user's historical usage; and an output for outputting an indication of a potentially fraudulent call based upon a result of the comparison performed by the comparator.
Abstract: An apparatus for detecting potentially fraudulent telecommunication activity, comprising a digital computer; interface, operatively connected to the digital computer, for receiving a call information record for each call involving a particular subscriber; comparator operating within the digital computer, for comparing a parameter of the particular subscriber's current usage with a subscriber-specific pattern of the particular subscriber's historical usage; and an output for outputting an indication of a potentially fraudulent call based upon a result of the comparison performed by the comparator.

212 citations


Patent
15 May 1992
TL;DR: The authors parse a user's natural language input into a case frame structure and filter the case frame into a goal-expression that comprises a verb and remaining syntactical portions of the natural language form input.
Abstract: A computer includes a data/knowledge base with a plurality of entries and further employs a user/computer interface for responding to a natural language form input. The interface, in combination with the computer, provides a help function that includes a browse search capability that responds to the natural language-form input by responding with matching knowledge base data. The method includes the steps of: parsing a user's natural language input into a case frame structure; filtering the case frame structure into a goal-expression that comprises a verb and remaining syntactical portions of the natural language input; providing each data/knowledge base entry with a goal-expression data structure that indicates a functional characteristic of the data/knowledge base entry; comparing the goal-expression with the goal-expression data structures to determine a match or matches; and paraphrasing the found matching goal-expression data structure or structures into a natural language-form and communicating the paraphrase or paraphrases to the user.

193 citations


Patent
05 Feb 1992
TL;DR: In this article, a system for providing an automatic interface between a host based, menu driven application program and a telephone network is described, which includes a host access table stored in a memory in the workstation, containing operational commands.
Abstract: A system is disclosed for providing an automatic interface between a host based, menu driven application program and a telephone network. The system includes a host access table stored in a memory in the workstation, containing operational commands. An interface program stored in the workstation memory executes the commands in the host access table, to perform interfacing functions between the host application program and the telephone network.

178 citations


Proceedings ArticleDOI
01 Jul 1992
TL;DR: The authors consider software and interface synchronization schemes that facilitate communication between system components and present tools to perform synthesis and simulation of a system description into hardware and software components.
Abstract: The authors consider software and interface synchronization schemes that facilitate communication between system components. They present tools to perform synthesis and simulation of a system description into hardware and software components. A program, Poseidon, is described that performs concurrent event-driven simulation of multiple functional modules implemented either as a program or as behavioral or structural hardware models. Input to Poseidon consists of description of interacting functional models with their respective clock cycle times and the interface synchronization scheme chosen by the partitioner. The resulting software component is assumed to be implemented for the DLX machine, a load/store microprocessor. Simulation examples and design of a graphics controller demonstrated the feasibility of mixed system synthesis. >

178 citations


Patent
03 Feb 1992
TL;DR: The Connection Machine® Computer CM-2 as discussed by the authors is a parallel vector machine model for building a compiler that exploits three different levels of parallelism found in a variety of parallel processing machines.
Abstract: The present invention provides a parallel vector machine model for building a compiler that exploits three different levels of parallelism found in a variety of parallel processing machines, and in particular, the Connection Machine® Computer CM-2 system. The fundamental idea behind the parallel vector machine model is to have a target machine that has a collection of thousands of vector processors each with its own interface to memory. Thus allowing a fine-grained array-based source program to be mapped onto a course-grained hardware made up of the vector processors. In the parallel vector machine model used by CM Fortran 1.0, the FPUs, their registers, and the memory hiearchy are directly exposed to the compiler. Thus, the CM-2 target machine is not 64K simple bit-serial processors. Rather, the target is a machine containing 2K PEs (processing elements), where each PE is both superpipelined and superscalar. The compiler uses data distribution to spread the problem out among the 2K processors. A new compiler phase is used to separate the code that runs on the two types of processors in the CM-2; the parallel PEs, which execute a new RISC-like instruction set called PEAC, and the scalar front end processor, which executes SPARC or VAX assembler code. The pipelines in PEs are filled by using vector processing techniques along the PEAC instruction set. A scheduler overlaps the execution of a number of RISC operations.

173 citations


Patent
10 Apr 1992
TL;DR: In this paper, a notepad has a form factor similar to a clipboard wherein the board portion includes a digitizing tablet and the clip portion includes an optical scanner, and a battery-powered embedded processor and associated peripherals provide for capturing and storing information in a variety of forms including at least scanning information, digitized stylus information and audio annotation.
Abstract: The novel notepad of the invention provides a convenient interface into the capabilities of computer technology from paper based information. The notepad has a form factor similar to a clipboard wherein the board portion includes a digitizing tablet and the clip portion includes an optical scanner. A battery-powered embedded processor and associated peripherals provide for capturing and storing information in a variety of forms including at least scanning information, digitized stylus information and audio annotation. An important feature of the invention is the linking of these different forms of information via software so that while the information is readily available for efficient processing, it is also combinable so as to recreate the annotated document through conventional means.

Patent
Paul H. Kramer1, Kay Anderson Tate1
30 Oct 1992
TL;DR: A data processing system include a plurality of data objects which are accessible by application programs through a system level interface as discussed by the authors. Each data object has an associated user access list, and each object has at least one key indicating which applications can access that object.
Abstract: A data processing system include a plurality of data objects which are accessible by application programs through a system level interface. Each data object has an associated user access list. In addition, each object has at least one key indicating which applications can access that object. The key is preferably maintained in a protected storage area, accessible only by the low level system interface. Both the application identifier key and the user who invoked that application must match the identifier information in the data object for access to be allowed to that object. If an unauthorized user attempts access to the data object through the correct application, or an authorized user attempts access through an incorrect application, access to the data object will be denied by the low level interface.

Patent
13 Feb 1992
TL;DR: In this paper, a telecommunications signalling interface for computer systems is presented, where control and information signals from the telephone switch are received, decoded, and converted to a standard interface format for retransmission to the computer.
Abstract: A telecommunications signalling interface for computer systems is presented. Control and information signals from the telephone switch are received, decoded, and converted to a standard interface format for retransmission to the computer. Control and information signals from the computer are received and converted to a standard format for transmission to the telephone switch. The power supply for the device may be derived from the telephone network and the computer interface.

Proceedings ArticleDOI
01 Dec 1992
TL;DR: This paper describes work to provide mappings between X-based graphical interfaces and auditory interfaces, and the design of an auditory interface which simulates many of the features of graphical interfaces.
Abstract: This paper describes work to provide mappings between X-based graphical interfaces and auditory interfaces. In our system, dubbed Mercator, this mapping is transparent to applications. The primary motivation for this work is to provide accessibility to graphical applications for users who are blind or visually impaired. We describe the design of an auditory interface which simulates many of the features of graphical interfaces. We then describe the architecture we have built to model and transform graphical interfaces. Finally, we conclude with some indications of future research for improving our translation mechanisms and for creating an auditory “desktop” environment.

Patent
15 Dec 1992
TL;DR: In this article, a multimedia system includes a multimedia device control program having a plurality of application program selectable controls for controlling operation of a like plurality of different classes of multimedia devices, each class has a different set of controllable device functions or attributes.
Abstract: A multimedia system includes a multimedia device control program having a plurality of application program selectable controls for controlling operation of a like plurality of different classes of multimedia devices. Each class has a different set of controllable device functions or attributes. In response to selection of a class by an application program, a unique control panel is created in a user interface for controlling operation of a device. The selected control performs all of the processing actions necessary to control the device in response to user selections on the interface, without involvement of the application program in such actions. The multimedia control program includes a plurality of panel templates from which control panels are created in a control screen. Each panel has a plurality of controllers that can manipulated by a user to control a corresponding function of a multimedia device. The templates provide a consistent interfaces having a common look and feel. The multimedia control program also includes a plurality of class control programs one or more of which are selected by an application program to be attached to a like number of multimedia devices for controlling operation of the devices in response to user selections on the user interface, thereby relieving the application program of performing the necessary control functions.

Patent
14 May 1992
TL;DR: A telephone terminal adapted for business or home use that includes the ability to receive and send facsimiles, a voice answering function and a computer modem is described in this article, where the facsimile is viewed on a video monitor or ordinary television set.
Abstract: A telephone terminal adapted for business or home use that includes the ability to receive and send facsimiles, a voice answering function and a computer modem. Various input and output devices may be used for the facsimile function. A voice annotated facsimile may be sent and received. At the same time the facsimile is viewed on a video monitor or ordinary television set, an accompanying voice message is heard through the sound system of the monitor or television set. The terminal has an architecture including a central processor and an internal bus structure to which several types of memory, various input-output devices and an interface with the telephone line are connected, among others.

Book
02 Jan 1992
TL;DR: Examines the use of audio, video, graphics, and animation in computer systems, specifically in the design and construction of the computer-human interface.
Abstract: Examines the use of audio, video, graphics, and animation in computer systems, specifically in the design and construction of the computer-human interface. Multimedia extensions to current computer systems allow us to employ our senses in new ways when interacting with the computer.

Patent
16 Mar 1992
TL;DR: In this paper, the authors describe a channel manager including a request dispatcher, request queues, a command initiator, and a plurality of state machines corresponding to state machines in the I/O devices.
Abstract: A device driver system comprises a core that manages the specific functions of a plurality of I/O devices. The core includes an operating system interface that is generic to different operating systems. An operating system has a device driver interface that is unique to the operating system. A conversion program is layered between the core and the operating system for converting communications between the device driver interface of the operating system and the generic operating system interface of the core. The core includes a channel manager including a request dispatcher, request queues, a command initiator, and a plurality of state machines corresponding to state machine in the I/O devices. A transport layer interfaces between the hardware and the channel manager.

Patent
30 Jan 1992
TL;DR: In this paper, a survey module is associated with the items incorporated in the interface, the module being arranged for displaying, in at least one survey window, an instantaneous synoptical table representing the constitution of all or part of the interface and composed on the basis of a descriptive status of the items.
Abstract: The method relates to the generation of interfaces that are structured around a window and can be displayed on the screen of a data processing system working in the graphics mode. The method is characterized in that a survey module is associated with the items incorporated in the interface, the module being arranged for displaying, in at least one survey window (16), an instantaneous synoptical table (18, 20) representing the constitution of all or part of the interface and composed on the basis of a descriptive status of the items (22), and that in the interactive mode, the creation and/or modification and/or incorporation of the items (22) is performed with the aid of at least one working window, preferably of the dialog window type, under the instantaneous control of the survey module. The invention also relates to an apparatus for performing this method.

Patent
02 Sep 1992
TL;DR: In this article, a ring interface is coupled to a media access control (MAC) block and the output of the MAC block includes a memory for packet buffering and is coupled with the primary memory.
Abstract: The present invention provides a method and apparatus for analyzing and monitoring network activity. The present invention provides one-hundred percent data capture for complete monitoring capability. The present invention also permits the simulated generation of traffic up to network capacity. The method and apparatus of the present invention allows for the use of pre-defined or custom-designed network tests so that users can analyze protocols and trouble-shoot network problems at various levels. Although one-hundred percent data capture is possible, the user may also customize the system to capture only certain packets of information. For example, the present invention can be implemented to capture errors, collisions and short-length packets. The present invention accesses the token ring network through a ring interface. The output of the ring interface is coupled to a media access control (MAC) block. The MAC block includes a memory for packet buffering and is coupled to the primary memory, which is coupled to the host interface. The output of the ring interface is also coupled to a serial state machine. The serial state machine is used for high speed decoding of packet information. The output of the serial state machine is coupled to a series of timers and filters tracking information from the data stream. An on-board CPU controls the timers and is coupled to the primary memory.

Patent
10 Mar 1992
TL;DR: In this article, a high-speed data packet switching circuit has a software controlled primary processing unit, a plurality of network interface units connected to plurality of networks for receiving incoming data packet streams and for transmitting outgoing data packet stream.
Abstract: A high speed data packet switching circuit has a software controlled primary processing unit, a plurality of network interface units connected to a plurality of networks for receiving incoming data packet streams and for transmitting outgoing data packet streams, a plurality of high speed data stream hardware control circuits for processing data packets in response to instructions from the primary processing unit and circuitry for interconnecting the primary processing unit, the interface units, and the data stream control circuits. The primary processing unit receives from the network interface unit at least a first one of the data packets of each new data packet stream and assigns that stream to be processed by one of the data stream control circuits without further processing by the primary processing unit. The apparatus and method thus perform routine, repetitive processing steps on the further packets of the data stream using the high speed hardware circuitry, while the initial processing and other non-repetitive or special processing of the data packets are performed in software. Particular hardware is described for effecting the high speed hardware processing of the data packets.

Dissertation
01 Jan 1992
TL;DR: Whole-hand input is a powerful tool for the real-time control of complex computer-mediated tasks that require the manipulation and coordination of many degrees of freedom as mentioned in this paper, and it can provide performance superior to that of conventional devices (such as dials, mice, and joysticks).
Abstract: This dissertation examines whole-hand input: the full and direct use of the hand's capabilities for the control of computer-mediated tasks. It presents the subject as a distinct study, independent of specific application or interface device. It includes a comprehensive discussion of the ideas, issues, and technologies relevant to the field. Whole-hand input is a powerful tool for the real-time control of complex computer-mediated tasks that require the manipulation and coordination of many degrees of freedom. By taking advantage of the innate naturalness, adaptability, and dexterity of the hand, whole-hand input techniques can provide performance superior to that of conventional devices (such as dials, mice, and joysticks) when applied to complex tasks. The important problems of whole-hand input involve appropriateness of use, control design, and device selection. The dissertation addresses these with a design method for whole-hand input by which an interface designer can discuss, develop, and evaluate techniques and devices for using whole-hand input in a particular application. Three experiments illustrate use of the design method and validate the principles of the thesis. A testbed and software library for investigating whole-hand input techniques is described. The testbed allows easy development and testing of whole-hand input with application simulations. The library is based on an abstract whole-hand input device type providing a standard interface to different physical whole-hand input devices. It features techniques for device calibration, posture recognition, and gesture recognition. Three prototype applications using the testbed, and one musical performance application demonstrate a variety of whole-hand input techniques including master-slave control, controlling task variables with hand shape, and gestural command input. The text concludes with detailed recommendations for future work to forward the understanding of the direct use of the hand as an input device. An accompanying videotape demonstrates the three experiments, the prototype applications, and shows a short section of the musical performance. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.) ftn*This work was supported in part by NHK (Japan Broadcasting Company), Defense Advanced Research Projects Agency-RADC Contract #F30602-89-C-0022, and equipment grants from Hewlett-Packard, Inc.

Patent
17 Sep 1992
TL;DR: In this paper, a data compression controller for processing data between a host system and at least one device is disclosed, which comprises a compression coprocessor for converting data between first format and second format at a determined controller ratio.
Abstract: A data compression controller for processing data between a host system and at least one device is disclosed. The data compression controller comprises a compression coprocessor for converting data between first format and second format at a determined controller ratio. The compression has two buffers for storing data of the first and second formats. When data is to be compressed, the coprocessor receives data directly from the host system into the first buffer. The coprocessor reads the buffered data and compresses the data for output to the external device through the second buffer. A coprocessor interface is coupled to the coprocessor for monitoring the buffers to determine the state of the buffers and the coprocessor; for example, if the such that the data to be compressed flows smoothly and consistently through the coprocessor. The input/output (I/O) controller is coupled to the coprocessor and the device for transferring data between the second buffer and the device. The I/O controller interface monitors the state of the I/O controller and provides the necessary control signals to indicate when to begin the transfer of compressed data to the device. In addition, the I/O controller interface configures and controls the I/O controller according to the device. Therefore, a single An application interface is coupled to the host system, for decoding commands from the host system, and issuing corresponding signals to the components of the controller to execute the commands. The application interface monitors the status of the controller through the I/O controller interface and the coprocessor interface and provides status information to the host system such that the host timely provides data to the coprocessor and the necessary commands to the application interface to maintain continuous movement of data through the coprocessor.

Patent
18 Nov 1992
TL;DR: In this paper, the authors present a method and apparatus for storing a Media Access Control (MAC) address in an EPROM disposed on a target interactive network board having a local area network interface.
Abstract: Method and apparatus for storing a Media Access Control (MAC) address in an EPROM disposed on a target interactive network board having a local area network interface comprises the step of activating a LAN communication program. The communication program operates to broadcast an inquiry through the LAN for the target interactive network board, to receive location information of the target interactive network board in response to the broadcast inquiry, and to establish communication with the target interactive network board. The MAC address is downloaded to a RAM on the board, verified therein, and loaded into the EPROM from the RAM.

Journal ArticleDOI
TL;DR: While the standard computer keyboard is an efficient interface for able-bodied people and some disabled people, it may present significant access problems for others, in these cases some alternative interface is necessary.
Abstract: Computers and computer-based technology have become an integral part of the lives of many individuals with disabilities. One of the most common activities that can be computer assisted is the generation of text. People who cannot accurately control their extremities (due to disabilities such as cerebral palsy and spinal cord injury) use computers as writing tools. People whose physical disability restricts their spoken output may use a computer as a communication prosthesis. In both cases, the generation of text is a necessary activity that can be physically demanding. It should be made as easy for the user as possible. While the standard computer keyboard is an efficient interface for able-bodied people and some disabled people, it may present significant access problems for others. In these cases some alternative interface is necessary.

Patent
26 Jun 1992
TL;DR: In this paper, a store data communications system, multiple data sources having disparate communications standards are connected with respective device interfaces of a multiple device communications controller unit, where multiple protocol controllers are coupled with the device interfaces and convert the data from each to a common protocol for transmission via a single telephone line.
Abstract: In a store data communications system, multiple data sources having disparate communications standards are connected with respective device interfaces of a multiple device communications controller unit. Multiple protocol controllers are coupled with the respective device interfaces and convert the data from each to a common protocol for transmission via a single telephone line. The interface units preferably can be customized to operate with various data sources, a fiber optic coupler, or a modem, or another controller unit for convenient expansion. The device interfaces preferably have snap-in assembly with the controller unit so that device interfaces customized to different standards can be inserted or replaced at any interface receptacle, the multiple protocol controllers preferably being capable of corresponding re-programming by downloading from a remote station preferably via one of the device interfaces.

Patent
07 Dec 1992
TL;DR: A power control device which incorporates a microcontroller to control the switching of power of a plurality of outlets is described in this article, where an operator communicates with the microcontroller through the computer's keyboard intercede to initiate a sequence of pro-programmed on/off events.
Abstract: A power control device which incorporates a microcontroller to control the switching of power of a plurality of outlets. A host computer communicates with the microcontroller through the computer's keyboard interface to instruct the device to turn on or off one or more of the outlets either immediately or at one or more preset future times. An operator communicates with the microcontroller through the computer's keyboard intercede to instruct the device to initiate a sequence of pro-programmed on/off events.

Patent
28 Jan 1992
TL;DR: In this paper, the authors present a method for improving the process of uploading data from a terminal computer to a host computer with interactive, data receiving screens using spreadsheet software to format data.
Abstract: Method for improving the process of uploading data from a terminal computer to a host computer with interactive, data receiving screens. The method features use of spreadsheet software to format data to be uploaded in a data source file. The data to be uploaded is laid out in single-row, multi-column form within the spreadsheet so that vivid, hard copy journals of the data may be created that facilitate examination of the data and memorializes its existence. Additionally, the data layout may be transformed and provided with additional information using the spreadsheet to create the data source file having a single-column, multi-row format suitable to facilitate entry of the data to the interactive screens for uploading. Additionally, the method features use of a management program that includes instruction for directing and coordinating the feeding of the data contained the source file to an interface program that enters the data in the predetermined fields of the interactive screens.

Patent
21 Apr 1992
TL;DR: In this article, a peripheral controller is described which is suitable for connecting a selected one of a plurality of peripheral devices to a computer system, which can be operated in an input only mode, an output only mode or a bidirectional mode and can be set into an appropriate mode by configuration control data sent from the computer system to the peripheral controller.
Abstract: A peripheral controller is described which is suitable for connecting a selected one of a plurality of peripheral devices to a computer system. The peripheral controller comprises programmable bidirectional line driver/receiver devices which can be operated in an input only mode, an output only mode or a bidirectional mode and which can be set into an appropriate mode by configuration control data sent from the computer system to the peripheral controller. The peripheral controller also includes a re-configurable logic array which can be configured under the control of the configuration control data to implement a particular interface required for the selected peripheral device. This increases the efficiency of use of a peripheral interface.

Patent
22 Dec 1992
TL;DR: In this article, a preferred interface circuit for interfacing between a digital-television circuit for producing pixel data for television images and a computer graphics display enables rapid scaling and positioning of live television images on the graphics display.
Abstract: A circuit for interfacing between a digital-television circuit for producing pixel data for television images and a computer graphics display permits rapid scaling and positioning of live television images on the graphics display. In a preferred embodiment, the digital-television/computer-graphics interface circuit of the invention includes memory for storing a horizontal-scaling bit pattern and a vertical-scaling bit pattern. Such a preferred interface circuit is adapted to receive digital-television pixel data from the digital television circuit and, on a pixel-by-pixel basis depending on the state of corresponding bits in the horizontal-scaling bit pattern, to skip the pixel in the case of image contraction and to replicate the pixel in the case of image expansion. The preferred interface circuit is also adapted to receive digital-television pixel data on a television-line by television-line basis and, depending on the state of a corresponding bit of the vertical-scaling bit pattern, to skip the entire line of pixel data in the case of image contraction or to replicate the line in the case of image expansion. The interface circuit may include a hardware vector generator for generating scaling bit patterns in accordance with a procedure analogous to a vector-drawing procedure used in graphics displays, such as the "Bresenham procedure."