Abstract: An address line arrangement which uses weighted sets of mutually independent rather than binary address lines to enable the accessing of any number of targeted elements at one time. The elements in a device are divided into groups of elements. For a numerical example, assume four elements per group and eight groups per device. One set of four address lines is wired to access one or all groups in one half of the device and a second set of four lines will access one or all groups in the other half of the device. A third set of four address lines is wired to all elements and will access one, two or all elements in each group at a time. Each element is wired to one line in the first or second group and one line in the second or third group. Since all address lines can be individually turned on, one or more elements can be accessed at one time.

Abstract: A circuit for implementing a substitutional compressor. Comparators compare a current input pixel against a large number of previous pixels, the "history", stored in a series of shift registers. Each register and associated comparator constitutes a cell. If one or more matches are found the history data is shifted one pixel, the non-matching cells are disabled, and the next input pixel is compared against the contents of the same cells that had the previous matches. The matching is terminated when the longest series of matching pixels is found. The output code is then the length of the matching series of pixels, and the displacement of the first input pixel from the first matching pixel. An encoder generates an initialize signal that resets all of the disabled cells on the same clock cycle on which the output code word is generated. To make the circuit more compact, the cells can be arranged into a square format with one output line for each row and column from the cells to the encoder.

Abstract: A searching and block access method on a digitally recorded continuous web media. The method enables a digitally recorded tape to be randomly positioned to access a specific requested data block. This method does not rely on scanning the information recorded on the tape to locate a requested data block. The tape is shuttled at high speeds to randomly requested locations. Tape positioning and control is accomplished by profiling the motion required to position the tape at the requested block relative to any current tape position. A tape directory of contents and tape position is recorded on the tape and cached within the drive controller. The cached version of the tape directory is used for random accesses. The random access ability enables the tape implementation to perform disk storage emulation.

Abstract: A system of managing a large number of complex versioned documents. Each document is given a tree structure such as document, chapters, sections and paragraphs. Also, the document is divided into locking units which can be individual nodes, such as one chapter, or subtrees such as one chapter and its three sections. Each locking unit must be checked out by the editing user, at which time it is not available for editing by any other user. Each locking unit contains pointers to the content of its nodes and to a shadow object for each node. The shadow object is allocated in unversioned storage, which does not have to be checked out. The shadow object contains pointers to its corresponding node, to clusters the node belongs to and to the nodes' parent node or nodes. This structure allows a user to reuse parts of a document in another document or include that part in a cluster even when the locking unit containing the part is checked out by another user.

Abstract: A combination of a tape cassette and a tape drive motor wherein a shaft is connected to a tape reel. A tape reel support is mounted to the housing of the cassette and a tape reel shaft extends through the support. Bearings are carried by the support for rotatably supporting the tape reel shaft and thereby the tape reel on the cassette housing. The motor has a rotor rotatable about an axis with the rotor being loosely mounted in the motor when a cassette is not in the tape drive. In one embodiment of the invention, the rotor carries a magnet which in combination with magnetically attractive material carried by the shaft, operates to connect the rotor to the shaft to effect a driving relationship between the rotor and shaft when the cassette is in the tape drive. The bearings on the cassette for the tape reel shaft served as the sole bearings for the rotor for rotational support when the rotor rotates and drives the shaft and thereby the tape reel.

Abstract: A bitmap-based digital color printing method and system is described which automatically detects when a black object is to be printed and changes the Bit Block Transfer (BitBlt) method so that the black color becomes a mixture of black plus the background colorants, limited by an allowed maximum non-black value for each separation. More specifically, the process determines, for each non-black separation, a maximum allowable amount to be used in black printing, reads the existing background color bits, and clips them if necessary to the allowed maximum before mixing them into the black color. The result will be a limitation on the total colorant amount of the black area, which improves some printer defects caused by too much colorant. The clipping can be accomplished at the bit level during the read-modify-write process if both the maximum and actual colors are represented with the same monotonic halftone dot specification, and are ANDed together to form the clipped bits.

Abstract: A bitmap-based digital color printing method and system is described which automatically detects when a black object is commanded to be printed, and changes the Bit Block Transfer (BitBlt) method so that the resultant composition of the black color at each point in the bitmap is responsive to the amount of non-black colorants already existing in the background color at that position on the page. For many printing systems the resulting prints exhibit fewer visual defects. Single-color black objects printed on top of a color field are printed as process black responsive to the background color. Therefore, they exhibit a greater density and gloss and show fewer problems caused by the misregistration of separations or other printer defects, such as white fringes around the black objects. They also avoid problems caused by excessive ink coverage differences between foreground black and background color.

Abstract: A computer controller for a raster output scanner. The software consists of an operating system and application programs. Each application program acts as a servo loop and controls such operating variables as the laser diode input power, output light intensity and temperature, and polygon speed. The operating system receives the current values of these variables, compares them against ranges limits and will inform the operator of malfunctions or needed maintenance in addition to managing the more typical computer functions such as driving peripherals and managing memory. The entire software system is generalized to the point where it can calibrate and maintain any ROS, and therefore need not be redesigned for different ROS products. In addition, when hardware parts are replaced, the operating system can change the operating ranges instead of replacing the programs.

Abstract: A system of creating enhanced reports from a computer database or programming language. The system will contain the basic data and some contextual information, which is the description of the type of information contained within the lists of the data file. The enhanced report generator will be sets of instructions which are loaded into the computer, each set of which will contain rules for formatting a report, based on the user inputs, the data, and the data's context. In the event that the context is not sufficient, additional contextual information will be loaded at the time that the enhanced report generator is loaded. The enhanced report generator will be loaded into the system in parallel with the standard report generator that is contained within the computer as a software application, and the user can select one, thus making the use of the enhanced reort generator transparent to the computer.

Abstract: A low cost, high speed, JPEG Huffman code decoder. The entire gamut of Huffman codes is partitioned into groups, with each group being associated with it's own small look up table to minimize the overall memory requirements. The current Huffman code is stored in a register. For the disclosed embodiment there are N=4 memories with sizes 128, 256, 128 and 256 elements respectively. For the specific typical Huffman code set cited, the partitioning is: The code words in the first group have 7 bits or less and are decoded in the first memory. The next group has from 5 to 7 leading ones, where the first five 1's are masked out and the remaining bits are used to address the second memory. The remaining codes have at least eight leading ones. Here, the first eight ones are masked out and the remaining bits are used to address the last memory. (In this example, one of the memories is not used).

Abstract: A lead edge lightening circuit which will lighten a scan line based on a seven by seven pixel area surrounding the current pixel. The area is divided into four sub-areas, each of four by four pixels, and each having the current pixel at one corner. Each sub-area is summed and compared to a threshold number. If the threshold number is equalled or exceeded by at least one of the four sums, an overlay bit, which can be white or black, is output. The current pixel is replaced by a white pixel if a white pixel has been output, otherwise the current pixel remains unchanged.

Abstract: A circuit for rotating a digital image through any angle at the rate of one pixel per clock period. First, the circuit divides the image to be rotated into blocks which can be rotated without pause once each is started. Then a nearest neighbor calculating circuit is used to determine the value of each rotated pixel in the block. The circuit is divided and pipelined so that each part can produce its output in one clock cycle. The nearest neighbor calculation is done in two sections of the circuit, and other sections of the circuit set up initial conditions or provide for transitions from one rotated scan line, or block, to the next.

Abstract: A digital color printing method and system is described which automatically determines a mixture of colorants to compose a process black color, taking into account relevent printing characteristics of a color printer and the background color at the point on the page at which the process black is to be printed. In certain printing systems, printing problems can occur when process black, composed of a mixture of colorants such as cyan, magenta, yellow, and black, is printed over a color background. For example, in a xerographic color printing system, a process black containing all colorants at maximum or near-maximum value can sometimes produce objectionable deletions in a surrounding color field, caused by interference in the transfer of toner to the background color field due to the process black toner pile height. Excessive combined toner pile height can also create an unevenness in the final print.

Abstract: A method of applying noise removal to an image so that the areas having the greatest variance have the least correction. First, the variance between each image pixel and its surrounding pixels is determined. Next, for the neighborhood around each pixel, a density of variance is determined. Finally the density of variance for the neighborhood around each pixel is used to correct the original pixel, the direction of correction being toward the mean value in the surrounding pixels. The result is that relatively uniform areas of the image, within which noise is most obvious, will get the most correction and areas that are textured will get the least.

Abstract: A printing system for printing several types of data on the same page, regardless of any differences in spot density between data types. This circuit provides a separate channel for each data type and processes each data type according to its own instructions and parameters (halftones, compressed images, font generation, etc) and according to its own spot density, without there being a necessity for there to be any synchronous relationship between x and y spot densities of the plurality of data types. Each channel has a boundary checker to determine whether the data is within the image boundary by comparing the x/y coordinates of the scanning beam to the input boundary data, and a data converter to convert the data according to its own instructions. Finally, the output of the channels is combined to form the data stream that is sent to the printer.

Abstract: A digital color printing method is described for printing process black over a background color, which makes use of color order information--that is, the order in which process colorants are transferred to paper--in determining and satisfying pile height constraints for optimal quality. In certain printing systems such as xerographic systems, printing problems can occur when process black, composed of a mixture of colorants such as cyan, magenta, yellow, and black, is printed over a color background. One such problem for example occurs when a process black containing all colorants at maximum or near-maximum value is printed on a color field. In this case, the excessive toner pile height of such a process black can sometimes cause objectionable deletions in the surrounding color field, caused by interference in the transfer of toner to the background color field surrounding the process black.

Abstract: A system for printing background and foreground colors in response to mask data and printing instructions. Page description language data is separated onto three lines, two for Contone and solid colors, and one for control (mask data and instructions). The mask and instruction data is transformed into a series of multi-bit command words, each describing a pixel in terms of 1) control tag bits to specify color, 2) object optimized rendering tag bits to describe the type of color (solid, text, sampled or line art), 3) color space transformation bits to control conversion from other spaces to CYMK and 4) format tags to specify the number of bits per pixel. This series of command words combines information on one line that required at least two lines in the prior art, and the data is in easily compressable form, resulting in simplified hardware.

Abstract: A halftone generator for generating tint dots that are more circular than typical Holladay dots. Two threshold arrays are used, one that is pixel-centered and one that is interstice-centered. For each signal input level, the one that will produce a more circular dot will be selected by a look-up table driven by the image signal input. A single array version can also be used. The stored array has pixel-centered thresholds at one end and interstice-centered thresholds at the other. The circuit can either choose an array output or an inverted array output to generate either pixel-centered or interstice-centered light and dark coverage.

Abstract: A digital color printing method is described for printing process black color over a background color, which modifies individual values of the process colors in a process black independent of other process colors whenever the black colorant is sufficiently opaque. An example described which controls excess total colorant in a process black while simultaneously controlling misregistration fringes, a result which is not possible with the standard approach of modifying all process colors uniformly. The result is obtained by preferentially reducing the process colorant value with the highest luminance instead of reducing all process colorants uniformly.In certain printing systems, printing problems can occur when process black, composed of a mixture of colorants such as cyan, magenta, yellow, and black (CMYK), is printed over a color background.

Abstract: Two sided electric paper that can be written onto on both sides by having a layer of conductive material between two sheets of electric paper. The electric paper is made of small balls encased in a liquid so that they are free to rotate, and then suspended in a solid substrate. Each ball has two hemispheres, one white and one black, each hemisphere also having a different electrical quality. Thus, in an electric field, the balls can be made to rotate to create an image of black and white areas. The intermediate conductor electrically isolates each sheet of electric paper so that both sides can be written onto at the same time.