Abstract: A method for directly measuring the area of a topological surface with an arbitrary boundary shape lying in a fixed elevation different from a fixed surrounding surface elevation relies upon binocular stereo vision. Three stereo correlation measurements are made, one over a window entirely within the surface of interest, a second over a window outside the surface of interest and within the surrounding area, and a third over a window fully containing the surface of interest as well as some of the surrounding area. The correlation measured in the third case is the linear sum of the correlation value over each of the first two cases weighted by the proportion of the window that the two surfaces occupy.

Abstract: A network of filter elements for transforming an analog signal of infinite bandwidth into a discrete filter space representation having a bandwidth equal to .pi.. In one embodiment the filter network includes Laguerre filter elements. Other embodiments include methods for estimating the values of the amplitudes, frequencies, and phases of the frequency components of the analog signal, for reconstructing an input signal, and correcting for non-ideal filter elements.

Abstract: A system for determining the s-plane parameters, s.sub.i and r.sub.i, of the transient response, ##EQU1## of a network-under-test (NUT). A filter bank, including N serially connected filter elements, has an input port and N output ports being the output ports of the filter elements. The system includes circuitry for sampling the response signal, at the N filter bank output ports. T seconds after a transient signal is received at the input port. A processor utilizes the values of the sampled response signal to determine the values of s.sub.i and r.sub.i.

Abstract: Apparatus for delaying an electrical signal includes a sequence of stages, each for delaying the signal. A coarser stage delays the signal by multiples of a predetermined fundamental delay interval and a finer stage provides for fine adjustment of the delay. The fine stage includes an integral number N of delay elements, the total providing a delay interval greater than the fundamental delay interval, whereby the fine delay intervals compensate for fabrication tolerances to enable accurate calibration of the combined system by post-fabrication measurement. In one implementation each delay stage includes a tapped transmission line to provide delay intervals, in another a ramp generator is used.

Abstract: A video stream processing system comprising a novel modular family of image processing and pattern recognition submodules, the submodules utilize a unique system signalling and interface protocol, and thus can be cascaded and paralleled to produce complex special purpose image processing systems which can operate at video or near video data rates. A stream of digitized pixel data is pipelined through a variety of submodules to support a wide variety of image processing applications. A common video interface provides for handling pixel data in the video signal path and a processor interface allows communication to any modern microprocessor for overall system control, for optional addition image processing and for defining options within each submodule.

Abstract: A method for determining the transfer function of a data acquisition system involves inputting a set of bilevel input test patterns to the system and measuring the system's response. The input test patterns from a complete orthogonal set. The input test patterns or the system's response can be weighted to correct for aliasing error and/or to represent any arbitrary input waveform. From the ratio of the Fourier transform of the sum of the responses to the Fourier transform of the sum of the input test patterns the transfer function is derived. In operation, the transfer function is used to accurately determine the characteristics of any input waveform to the system.

Abstract: A printer/plotter incorporates four individual microprocessor-based print stations, each for printing on a print media a separate color image for superimposition with one another, forming a final full-color image. The four print stations are located along a transport path for single-pass operation, and each print station includes a transport system that allows the media to traverse a print station with controlled forces exerted on the media by that station. The invention further includes a precise registration system wherein each print station monitors registration marks to detect variations of the media (i.e., stretching or shrinkage) during the printing process and to correct for such variations on obtaining accurate registration of the individual images for a full-color result.

Abstract: A video stream processing system frame buffer controller for controlling external dynamic random access memory (DRAM) of a frame buffer and interfacing to the video stream processing signal bus. The frame buffer controller has four interfaces, video input interface, video output interface, memory interface and processor interface. The circuit can input image data from a camera and store the frames in external DRAM. The circuit provides for external processor access to pixels in the frame buffer and for output of the frame or portions of the frame, as well as output of frames in a format of CRT display and external DRAM refresh.

Abstract: An image processing system for computing morphological characteristics of object regions in a binary image frame. The characteristics are generated at the frame rate. One embodiment utilizes an architecture including an interconnected delay component, bit packing component and LUT. The output values provided by the LUT are accumulated over one frame cycle to compute morphological characteristics.

Abstract: A high precision analog to digital converter comprises the combination of an imperfect or low resolution digital to analog converter having an error function known in terms of orthonormal components and an error compensating device capable of generating correction terms which do not interact with one another. The correction terms are based on orthonormal components namely, the Walsh function components, of each signal level to be compensated. At most only one weighting value per bit is required, the combination of which will compensate for errors of any bit combination. In a specific embodiment employing feedback compensation, the output of the low resolution converter and of the compensating device may be summed to produce a high performance, high precision converter with increased accuracy and resolution.

Abstract: A simulation system for visual signal processing circuits is presented which provides a detailed, pixel level analysis of the timing while actually performing the simulation at the frame level. Input to the circuit is the form of images captured by a video camera. The processing of a frame of image data by each circuit component is simulated and the resulting frames of image data are stored until they are no longer needed by other components. The output of the simulated circuit is displayed on a monitor.The timing of the circuit is analyzed for distinct groups of components which must operate in synchronism. Scaling factors are calculated for each net in the group from the incremental scaling rate of each component and the connectivity of the circuit. The scaling factors indicate the relative rate at which value pixels arrive at each net. The time at which a reference pixel arrives at each net is then computed to ensure that corresponding pixels arrive together at components with multiple inputs.

Abstract: An arithmetic logic system for performing a variety of arithmetic and logical functions on pixel input streams such as averaging down the input image stream, computation of absolute values, and signed or unsigned, clipped or unclipped, addition, subtraction and multiplication. The arithmetic logic system has a first arithmetic logic unit connected to a plurality of input signals. A second arithmetic logic unit is coupled to the first arithmetic logic unit and operates on the output of the first arithmetic logic unit. A control unit is coupled to the first and second arithmetic logic units and controls the operation of the second arithmetic logic unit based on the output of the first arithmetic logic unit.

Abstract: A memory system for storing and retrieving data sequences of symbols in response to a query sequence is disclosed. Each of the sequences is made up of three types of symbols, constants, delimiters, and variables. A data sequence is retrieved in response to a query sequence if the two sequence can be made identical by replacing the variables in each sequence by constants or combinations of constants and delimiters, the combinations beginning and ending with a delimiter. To reduce the time needed to search the memory for all data sequences corresponding to a given query sequence, multiple processing units are employed. In addition to carrying out rule-based searches, the memory system can efficiently retrieve all records containing a specified list of key words.

Abstract: A process for signal matching. The process is general and can be applied to matching signals of arbitrary dimension. To implement the process, a suitable discretized description of the two signals to be matched is defined. Such descriptions can be the local signal extrema or any other qualitative signal significant points of interest or features. Allowable feature matches and values for matches are defined, and determined for all potential matches. Matches are confined to the features within defined matching windows and are mapped for each significant point. Within a defined similarity disparity window, a neighborhood of potentially interacting matches are evaluated. Matches within a neighborhood contribute to the decision about the appropriate match for each significant point to determine a composite similarity weighted best value match for each point. Mapping is piecewise continuous. The two signals are matched with disparities therebetween resolved and removed responsive to the best match values.

Abstract: Disclosed are a method and a system for processing patterns such as oriented patterns, to derive constituents which are more useful than the original patterns. For example, an oriented pattern such as a seismic section can be decomposed into a flow field, which is an estimate of a moving accretion boundary which formed the subsurface layers, and a residual pattern, which is an estimate of layer properties, such as acoustic velocity. Similarly, an oriented pattern such as a chart displaying changes in borehole resistivity with depth along its vertical direction and changes in resistivity with angle around the borehole along its horizontal dimension, can be decomposed into a flow field and a residual pattern, where the flow field is an estimate of a moving accretion boundary and the residual pattern is an estimate of resistivity changes with depth and angle independent of the accretion boundary. The flow field can be mapped onto regular, e.g.

Abstract: A subsystem component for use in an image processing system to compute a gray scale histogram function or various statistical functions relating to the coordinates of a region or regions in a binary image. A selected function is computed at the video rate of frame generation.

Abstract: A method for determining the position of media in a system where images are applied to the media at subsequent stations includes the steps of placing on the media at a first position tracking information consisting of a pattern of electrostatic charge to provide information with regard to the alignment of the media at the first station, and at the second station detecting the pattern of electrostatic charge to determine the alignment of the media at the second station. Typically the media consists of electrostatic paper and the step of placing charge on the paper is achieved by positioning positively charged styli in close proximity to the surface of the paper.

Abstract: A color printer/plotter includes a frame having a paper inlet, a number of print stations, and a paper outlet. The paper is pulled past the print stations by a single driver at the paper outlet. Each print station includes a electrostatic charging head having a flat charging surface against which a first roller, typically having a foam outer surface, presses with the paper therebetween. Immediately downstream of the charging head a toner roller supplies toner to the paper, the toner adhering to the charged areas on the paper. A second pressure roller presses the paper against the toner roller. The second pressure roller is offset slightly upstream of the center of the toner roller to aid toner roller-paper contact. The sizing and positioning of the toner and second pressure rollers is such so as not to significantly deflect the paper from the substantially straight paper path between the paper inlet and paper outlet.

Abstract: An assembly for mounting a roll of paper or Mylar.RTM. film having a hollow core includes a radially expanding core insert at each end of the roll and a core insert support, mountable to a support structure, to support, position and apply a drag force to the paper roll. Each core insert has a radially expandable inner end which is expanded within the core to secure the insert in place. The outer end of the core insert extends beyond the edge of the paper roll. The core insert support includes a pair of arcuate contact surfaces and an adjustable spring biased brake shoe mounted to a frame. The brake shoe presses the outer end of the core insert against the contact surfaces to create a suitable drag on the paper roll. A flipper is pivotally mounted to the frame for movement between free movement and blocking positions to permit or prevent the core inserts from being removed from the core insert supports. Each flipper also axially biases the core insert towards the other flipper.