Abstract: In order to reduce the size of an apparatus capable of obtaining a result of correlation between images at a high speed, a multiplex selector for shifting addresses of a plurality of memories, a detector for detecting an amount stored in a memory element of one of the plurality of memories and an amount stored in a memory element obtained by shifting an address of the one of the plurality of memories, and a determination unit for obtaining correlation between outputs of the detector for each amount of shift.

Abstract: A system for creating an index print, generated from a negative strip having one or more frame images, independent of sequentially scanning each frame on the negative strip, the system includes a scanner for substantially simultaneously creating a composite digital image of the negative strip from the negative placed on the scanner independent of the position or orientation of the negative on the scanner. An image locator operatively connected to the scanner for locating each digital representation in the composite digital image of the individual frame images on the negative strip. A printer operatively connected to the locator for printing the index print from a signal from the locator.

Abstract: An arrangement is described for determining the skew angle of a document image without requiring text or other skew detection information in the document or without human intervention. The arrangement accomplishes this by determining an edge of the document image within a scan image and uses that edge to determine the skew angle of the document image. The edge can be determined by locating the first or last document image pixel of each scan line of pixels in the scan image that belongs to the document image. This is accomplished by comparing each pixel of each scan line of pixels with a predetermined scan line of background pixels. The skew angle of the document image is then determined by computing the slope of the detected edge in the scan image. An arrangement of determining the boundary of the document image is also described.

Abstract: A method for determining extrema of an object with respect to a reference frame that is rotated in comparison to that of the image and the equipment that acquired it is characterized by the steps of taking a first projection of the object with respect to an axis of a coordinaate system that is rotated with respect to the reference frame of the acquisition equipment, identifying in that projection locations representing extrema of the object, and outputting those locations as indicative of the extrema with respect to the axis.

Abstract: An automatic image data aligning technique for an image processing apparatus, such as a facsimile machine including the steps of assigning coordinates corresponding to horizontal and vertical lines of the document to be sent as the document is scanned with a laser beam, reading out a fiducial coordinate value of the horizontal line in the document, and computing and storing the respective compensatory coordinate values of the image data's horizontal lines; reading out a fiducial coordinate value of the image data's vertical line and computing and storing the compensatory coordinate values of the image data's vertical line; and aligning the image data's coordinates by using the respective compensatory coordinate values of the horizontal and vertical lines.

Abstract: An automated method and system for determining the positional orientation of radiographic images, wherein digital image data is acquired and subjected to multiple phases of digital imaging processing. The image is processed to segment the object of interest, i.e., a body region, from the foreground and background of the image. Next, the center is determined for the body region. The body region center is then positioned so that it coincides with the center of the film or medium. The image is subsequently decomposed into one or more horizontal and vertical strips. Feature extraction is performed on these strips to preliminarily determine the orientation of the image. Finally, a set of rules is applied to the image information described above to determine the positional orientation of the image.

Abstract: Apparatuses and methods are provided for locating and straightening horizontal and vertical lines in digitized documents by first identifying horizontal or vertical elements, each of which may represent part of a longer line, according to several adjustable criteria. This approach confines use of precise, computationally intensive line-fixing routines to image regions likely to contain a line. In one aspect, the invention performs pixel-by-pixel scanning only in those regions likely to contain a line segment. Given a threshold number of pixels defining the smallest possible line segment, the invention begins with an initial pixel and tests the pixel linearly displaced therefrom by a distance equal to the threshold. If the displaced pixel is uncolored, a consecutive threshold-length run of colored pixels cannot exist between the initial and displaced pixels, so all of these pixels are considered evaluated and the displaced pixel becomes a new initial pixel.

Abstract: Image registration is performed by reducing images to histograms, rotating histograms to register the histograms, then using the registration of the histograms to register the images, thereby registering images with less computation than image rotation. Where the image is compressed using line-by-line run length encoding, the histogram can be derived from the run length encoding without decompression. Histogram rotation can also be used for skew angle detection.

Abstract: A system and method automatically detects user defined zones in a document image of a form, compensating for skew and displacement of the image with respect to a original image of form. The system provides a mechanism to input an image for a form document, such as a scanner. The system processes the image to reduce its resolution and to remove significant skew. The image is presented to the user to define the zones. These zones are areas from which the user desires to extract meaningful data through optical character recognition, such as names, dates, addresses, and items on a invoice form. The system further processes the image to remove horizontal and vertical lines, and to create a number of blocks, representing either text or image data. The lines are removed and the blocks formed by runlength smoothing with various parameters. The blocks form clusters of connected pixels. The blocks are labeled such that any set of connected blocks share a unique identification value.

Abstract: The present invention relates in general to optical scanning and image processing, and relates more particularly to a document imaging system which detects skew and/or detects size/shape of a document image. Preferred embodiments utilize a background with optical characteristics which contrast with those of the scanned document. In one embodiment, a document imaging system generates scanning signals in response to optical characteristics of a medium such as a sheet of paper, detects transitions in the scanning signal which define points along one or more edges of the medium, establishes a skew angle between the detected edges and a reference orientation, and compensates for skew by modifying the scanning signals as required such that the resultant skew angle is substantially equal to zero.

Abstract: An apparatus for separating an image from a black frame quickly and precisely wherein corner coordinates for a character field are inferred by using a parameter relative to a character frame layout, and more precise corner coordinates are detected by pel distribution in a partial range. The positions of inner walls of a black frame are then inferred by using the detected corner coordinates and the parameter relative to the character frame, and a detection area is set. The positions of the inner walls are precisely detected by the pel distribution in the detection area, and smoothing process is performed on the detected values by employing the detected values of other adjacent black frames. Sequentially, white lines are drawn along the inner walls to separate the black frame from the character, and noise is removed. In consonance with a skew value, the detection area is divided to change the set range, and data separation is performed by using two white lines with a step difference between them.

Abstract: A method, apparatus and computer program product for extracting the line of text to be read, and compensating for any inclination or shifting in the column direction of the scanned character images, to improve the recognition ratio of the character recognition process. By extracting the characters at or near the column-direction center of plural meandering lines of scanned character images, the lines intended to be read for character recognition can be extracted based on the extracted characters. When there is shifting in the column direction between character images on the same scanned line, the amount of shifting is determined based on the inclination between the characters to compensate the shifting based on the obtained inclination. When the scanned character images are skewed relative to the column direction, a process minimizing the slope of the inclination is executed to compensate the inclination.

Abstract: A platenless book scanner with line buffering performs electronic perspective correction to account for rotation of the spine of a non-planar bound document relative to a reference line in a support plane of the platenless book scanner. A pre-scan of the non-planar bound document is performed to provide a geometrical contour map of the bound document. The geometrical contour map, which identifies displacement of the bound document from the support plane, is analyzed to calculate an angular offset between a spine of the bound document and the reference line in the support plane. The angular offset is used to identify a minimum number of scan line buffers for recording image data, from a set of scan line buffers. Once the minimum number of scan line buffers is filled with recorded image data, distortions caused by displacements of the non-planar bound document from the support plane and skew of the bound document relative to the reference line in the support plane are corrected.

Abstract: A deflection device allows deflection correction control of suspended cargo for deflections having both parallel deflection and skew deflection components. The suspended cargo is held by a suspension tool suspended from a trolley via ropes and is carried together with movement of the trolley. The device has mark detectors provided under the trolley with a range of vision facing downwardly and a corresponding plurality of marks provided opposite of the mark detectors on the suspension tool. A picture processing device generates picture signals of the first and second marks detected by the mark detectors. A deviation amount computing device calculates the deviation of the first and second marks, and a deflection amount calculating device calculates the amount of parallel deflection and the amount of skew deflection based on the computed deviation amount.

Abstract: A method is provided for identifying, correcting, modifying and reporting imperfections and features in pixel images that prevent or hinder proper OCR (Optical Character Recognition) and other document imaging processes. One embodiment of this invention provides that run length compressed images can be analyzed and corrected directly for improved performance. Major steps included in this invention for the enhancement of images for OCR and document imaging are: The detection of undesired printed matter and the deletion of undesired printed matter. Detection of undesired printed matter includes successive generation of entries into an array listing of undesired printed matter to be deleted. Deletion of undesired printed matter follows in a separate step for all types of undesired printed matter.

Abstract: An image of an original mounted on a platen is converted into image data by a CCD. An original region detection unit detects the region of the original mounted on the platen from the image data. According to this detection, the writing address of the image memory is controlled so that image data of the center of the original mounted region is written into an address matching the center of the sheet. As a result, various image editorial processes can easily be carried out in a digital copy machine.

Abstract: A double four-quadrant angle position detector is disclosed. The angle position detector comprises a first orientation detector, a second orientation detector, and a detecting means. The first orientation detector is composed of two pairs of photo-detecting means, arranged on opposite sides along vertical and horizontal directions, respectively, to generate output currents according to the brightness level. Similarly, the second orientation detector can also generate output currents according to brightness level. The detecting means determines a first angle and a second angle according to these output currents and then compares the difference of the first angle and the second angle with a preset threshold. When the difference is greater than the preset threshold, it indicates that an image angle is passing through the sensor.

Abstract: The techniques for determining the orientation of lines in images disclosed herein take as their starting point an apparently universal typesetting convention: that symbols are generally closer to other symbols in the line to which they belong than they are to symbols in other lines. The techniques make a graph by connecting symbols in an image of a block of text with edges (lines) and then determine the predominant orientation of the shortest edges. Because the symbols in a line are closer to each other than to symbols in other lines, the predominant orientation of the shortest edges will be the same as the orientation of the lines. An advantageous mode of obtaining the shortest edges is to construct a Euclidean minimum spanning tree from the graph. A Euclidean minimum spanning tree of a graph contains all the nodes (symbols) of the original graph but connects the nodes with the shortest possible set of edges. The edges which predominate in the Euclidean minimum spanning tree are the shortest edges.

Abstract: A visual gyroscope system for detecting turns and straight line travel of a vehicle includes a visual image detector mounted on the vehicle, for producing sequential and successive digitized image data strips containing information identifying scenery about the vehicle at associated successive locations along the route travelled, A processor is programmed to extract from image detector each successive pair of image data strips, and rotate the second occurring strip of each pair until it matches the first occurring strip to obtain the incremental rotation and direction of rotation of the vehicle in its travel between strips. The incremental rotations between strips are accumulated and summed to obtain the total rotation upon completion of a turn, and along with the direction of rotation, identification of a right turn, left turn, u-turn, or straight line travel.

Abstract: To determine the orientation of a set of recorded images, the recorded images are scanned. The scanning operation obtains information regarding at least one scene characteristic distributed asymmetrically in the separate recorded images. Probability estimates of orientation of each of the recorded images for which at least one scene characteristic is obtained are determined as a function of asymmetry in distribution of the scene characteristic. Probability of orientation for the set of recorded images is determined from the probability estimates of orientation of each of the recorded images in the set.

Abstract: An area discrimination system discriminates areas from each other in a binary image. The system includes a reducing unit for reducing a binary image supplied from an external unit, a skew detector for detecting skew of the binary image with respect to a predetermined direction, an extracting unit for extracting black connected components from the reduced image, a block forming unit for forming blocks, each of which includes a plurality of black connected components close to each other, a first merging unit for merging blocks satisfying first conditions into a a character string by using of the skew detected by said skew detector, the first conditions including at least a condition depending on skew of the binary image, and a second merging unit for merging character strings satisfying second conditions into a column by using of the skew detected by said skew detector, the second conditions including at least a condition depending on skew of the binary image.

Abstract: The process for enhancing images of scanned documents identifies a variety of items in the scanned document which could make optical character recognition and other document image processing difficult or impossible. These items include identifying skew, registration, speck, lines intersecting printed matter, reverse printing, shaded printed matter. The process allows to register such items, take steps to correct skew and image registration, as well as reverse invert printing. Items to be removed are listed for deletion in one step. The image of the scanned document is stored and processed as a run-lngth coded image, except for a some operations in which parts of the run length coded image are converted to pixel image code for particular substeps of the process. The result of such a substep, e.g. a modified image, is then re-converted to run-length code.

Abstract: A process for determining an orientation of a binary image includes segmentation of the image into many square regions. Orientations of the individual regions that are determined to be textual squares allow local variations of the binary image to establish an overall orientation for the binary image. The process iteratively groups and consolidates the individual regions into successively larger and larger regions. An orientation for particular ones of the larger regions is determined by a single mode of the various composite modes of the particular one regions having the greatest weight. After all the regions have been consolidated in this fashion, the process uses the orientation of the single consolidated region as the orientation of the binary image.

Abstract: A method and apparatus for detecting the skew angle of a document image. Skew angle determination is performed by the steps of determining a set of sampling points from an input document image and processing X and Y coordinates of the sampling points in order to calculate a regression coefficient of the sampling points. The skew angle of the document is determined using the regression coefficient. To evaluate a calculated skew angle which corresponds to the regression coefficient, a correlation coefficient is calculated and evaluated. As coordinates of sampling points are obtained for a plurality of sets of data corresponding to different ruled lines or lines of characters, a histogram may be used to determine the most probable skew angle.

Abstract: A method of locating an object which has a straight edge is disclosed. An illustrative embodiment of the invention orients the object's edge so that it is at an oblique angle to the axis of the coordinate system of the sampling plane of the input device scanning the object. A subset of the pixels associated with the object's edge are identified and used to estimate the location of the object or edge.

Abstract: A system electronically registers an image on an input document. The system includes a scanner for generating an image data stream representing an electronic image of the image on the input document and an edge detecting circuit for detecting edge data within the image data stream. A circuit calculates a skew angle of the input document based on the detected edge data and rotates the electronic image based on the calculated skew angle to register the electronic image with an output medium. The system also includes a non-image area generating circuit for generating areas in the electronic image which correspond to non-image areas based on the calculated skew and detected edge data. The skew calculation, rotation operation and the non-image area generation is based the electronic detection of the corners and center of the leading edge of the document being scanned.

Abstract: A processor measures size or spacing of connected components for an image of text by obtaining a distribution of measurements of distances between edges of connected components. The distances are measured along lines extending in a measuring direction, such as a direction parallel or perpendicular to lines of text, which can be determined based on a measurement of skew. The distance measurements then can be used to produce a distribution of measurements as a function of distance, such as a histogram. Sufficient distances are measured that the histogram or other distribution data indicates a measure of size or spacing of connected components for the image, such as a stroke width, a maximum character width or height, or a spacing between characters, words, or lines. To measure sizes, distance can be measured across pixels within connected components. To measure spacings, distance can be measured across pixels that are not within connected components.

Abstract: A document skew detection apparatus for facilitating the recognition of the contents of a printed document includes an image processing section for generating a binary coded image of the document containing a plurality of black picture elements distributed among white picture elements to depict pure text lines and non-text portions of the document. The binary coded image is then modified so that certain ones of the black picture elements satisfying a predetermined condition are integrated together to generate a coarse document image being decreased in resolution. The apparatus also includes an image extraction section for extracting from the document image a local image region containing pure text lines occupying an almost entire area thereof, and skew detection section for detecting a direction of orientation of the text lines of the local region, and for determining an angular difference between a detected direction and a reference direction as a skew angle of the printed document.

Abstract: A data converting apparatus mainly includes: a memory part for storing at least one set of outline data representative of an outline of one character which includes at least one straight line segment; a first determining part for comparing each of the at least one straight line segment with a predetermined reference direction and for determining whether the corresponding straight line segment has an orientation sufficiently similar to the orientation of the predetermined reference direction; a second determining part for determining whether a offset error produced when the straight line element determined by the first determining part is converted to a dot image deviates from a predetermined tolerance range; and a correction part for correcting the straight line segment determined by the second judging part so that the offset error of the straight line segment does not exceed the tolerance range; and filling-in part for converting the outline data including the straight line segment corrected by the correctio