Abstract: A projection display device including: an image light projecting unit that projects image light on a screen; a distance measurement unit that measures distance to the screen; an obstacle detecting unit that detects an obstacle between the screen and the image light projecting unit on the basis of distance information obtained by the distance measurement unit and, according to a result of this detection, determines an adjustment area where the image light to be projected is to be adjusted; and a projection adjusting unit that adjusts the image light in the adjustment area are included.

Abstract: A projection display device including: an image light projecting unit that projects image light on a screen; a distance measurement unit that measures distance to the screen; an obstacle detecting unit that detects an obstacle between the screen and the image light projecting unit on the basis of distance information obtained by the distance measurement unit and, according to a result of this detection, determines an adjustment area where the image light to be projected is to be adjusted; and a projection adjusting unit that adjusts the image light in the adjustment area are included.

Abstract: There are provided a data recording medium, a reading device for reading the data recording medium, a recording device for reading the data recording medium and recording data to other media, and methods thereof able to prevent forgery without comparing visible information and data stored in a built-in electronic circuit chip. The reading device is for reading a data recording medium including a sheet portion visibly printed with an image and a data storage unit recorded with control data.

Abstract: An image detecting method comprises the steps of: a) searching for a pattern satisfying a predetermined commencement requirement by scanning an input image; b) using the pattern as a starting point, with referring to a dictionary storing therein distances between the center line and an edge of a detection target semicircle, determining for each of a predetermined number of main scan lines along a sub-scan direction whether or not a predetermined edge pattern occurs within a respective range of the distance of the dictionary; and c) determining a detection of the semicircle when the number of error lines on which the predetermined edge pattern does not occur within the respective range of the distance of the dictionary is less than a predetermined threshold.

Abstract: There are provided a data recording medium, a reading device for reading the data recording medium, a recording device for reading the data recording medium and recording data to other media, and methods thereof able to prevent forgery without comparing visible information and data stored in a built-in electronic circuit chip. The reading device is for reading a data recording medium including a sheet portion visibly printed with an image and a data storage unit recorded with control data.

Abstract: An image detecting method comprises the steps of: a) searching for a pattern satisfying a predetermined commencement requirement by scanning an input image; b) using the pattern as a starting point, with referring to a dictionary storing therein distances between the center line and an edge of a detection target semicircle, determining for each of a predetermined number of main scan lines along a sub-scan direction whether or not a predetermined edge pattern occurs within a respective range of the distance of the dictionary; and c) determining a detection of the semicircle when the number of error lines on which the predetermined edge pattern does not occur within the respective range of the distance of the dictionary is less than a predetermined threshold.

Abstract: An original image comprises a printed region on which a predetermined printed matter is realized and a background region on which no printed matter is realized. The shape of a peripheral zone in the original image comprises the shape of the background region, which shape exists particularly at the peripheral region of said original image. It is determined whether or not the original image comprises the special document by detecting the peripheral zone. Further, the original image has an outer-frame region, having a predetermined shape at the peripheral region of the original image. The determination is carried out using a result of measuring the width of the outer-frame region. Further, the width of the outer-frame region comprises a width along a direction substantially perpendicular to a direction extending along the outline of the original image.

Abstract: An image recognition apparatus for recognizing a specific image in an object image using image signals of the object image, the specific image having a possibility of being rotated. The image recognition apparatus includes an image information extraction unit for extracting an object image from the image signals as a candidate for recognition of the specific image and for extracting feature values from the object image using the image signals, and a match determining device coupled to the image information extraction unit for recognizing the specific image in the object image by a comparison of the extracted feature values from the object image with reference data for the specific image. The match determining device is controlled using the reference data according to an easy to determine rotation characteristic and difficult to determine rotation characteristic in the reference data for the specific image.

Abstract: An image pattern recognition process and system recognize a rotated predetermined image pattern with reduced processing time and memory requirements based upon the efficient use of the Zernike Moment.

Abstract: A circumscribing rectangle is obtained for a black continuous image part using a two-tone image signal. If it is determined that the image part is possibly one which is obtained as a result of rotating the object, lengths of sides of the image part are compared with threshold values. If it is determined that the image part is not one which is obtained as a result of rotating the object, the height and horizontal length of the circumscribing rectangle are compared with the threshold values. Thus, it is determined whether or not the image part is identical to the object. An RGB chromaticity histogram is produced for each of small regions of an input color image. Each of the chromaticity histograms of the small regions is compared with reference ones. As a result of the comparison, an identification number of the reference histogram having the highest similarity to that of the small region among those constituting the input image is given to the small region.

Abstract: A circumscribing rectangle is obtained for a black continuous image part using a two-tone image signal. If it is determined that the image part is possibly one which is obtained as a result of rotating the object, lengths of sides of the image part are compared with threshold values. If it is determined that the image part is not one which is obtained as a result of rotating the object, the height and horizontal length of the circumscribing rectangle are compared with the threshold values. Thus, it is determined whether or not the image part is identical to the object. An RGB chromaticity histogram is produced for each of small regions of an input color image. Each of the chromaticity histograms of the small regions is compared with reference ones. As a result of the comparison, an identification number of the reference histogram having the highest similarity to that of the small region among those constituting the input image is given to the small region.

Abstract: A reference-character size determination unit determines a reference-character size based on a distribution of sizes of particular continuous image parts, the continuous image parts constituting an image. An image part sorting unit sorts the particular continuous image parts into character image parts and other image parts based on the reference-character size. A rectangle determination unit determines a rectangle for each continuous image part, a size of the rectangle corresponding to a size of the corresponding continuous image part. The reference-character size determination means determines the reference-character size based on a distribution of sizes of the rectangles. The image part sorting means sorts the particular rectangles into rectangles for the character image parts and rectangles for the other image parts based on the reference-character size.

Abstract: An original image comprises a printed region on which a predetermined printed matter is realized and a background region on which no printed matter is realized. The shape of a peripheral zone in the original image comprises the shape of the background region, which shape exists particularly at the peripheral region of said original image. It is determined whether or not the original image comprises the special document by detecting the peripheral zone. Further, the original image has an outer-frame region, having a predetermined shape, at the peripheral region of the original image. The determination is carried out using a result of measuring the width of the outer-frame region. Further, the width of the outer-frame region comprises a width along a direction substantially perpendicular to a direction extending along the outline of the original image.

Abstract: The present invention relates to a special-document discriminating apparatus used for providing a counterfeit preventing function to a digital copy machine and the like, and to a managing system for an image forming apparatus having a special-document discriminating function. The special-document discriminating apparatus is provided with a ROM for discriminating a special-document such as paper money, which ROM is detachably attached to a controlling circuit board. Data used for determination may be learned from test pattern data input from the image forming apparatus, or the data may be input from an external unit via a communication line. The managing system for an image forming apparatus comprises an image forming apparatus and a managing apparatus connected to the image forming apparatus. Either the image forming apparatus or the managing apparatus has a special-document discriminating function.

Abstract: The present invention relates to a special-document discriminating apparatus used for providing a counterfeit preventing function to a digital copy machine and the like, and to a managing system for an image forming apparatus having a special-document discriminating function. The special-document discriminating apparatus is provided with a ROM for discriminating a special-document such as paper money, which ROM is detachably attached to a controlling circuit board. Data used for determination may be learned from test pattern data input from the image forming apparatus, or the data may be input from an external unit via a communication line. The managing system for an image forming apparatus comprises an image forming apparatus and a managing apparatus connected to the image forming apparatus. Either the image forming apparatus or the managing apparatus has a special-document discriminating function.

Abstract: An image forming apparatus including an image reading unit for reading an original and for outputting image data corresponding to the original, an image processing unit for processing the image data supplied from the image reading unit in accordance with a predetermined method and for outputting printing image data, a printer unit for printing an image corresponding to the printing image data supplied from the image processing unit, and an image adding unit for adding an identification information to the recording sheet on which the image is formed by the printer unit, the identification information identifying the image forming apparatus in order to prevent forgery of securities, confidential documents or backnotes. A detector detects the presence or absence of the image adding unit and disables the copying functions when the image adding unit is absent.

Abstract: A binarization method obtains an optimum threshold value for binarization which is used when converting a multi-level image data which describes an input image into a black-and-white bi-level image data. The binarization method includes the steps of counting a first number of black picture elements by varying a threshold value from a darkest tone level to a lightest tone level, counting a second number of picture elements having a tone level other than the lightest tone level, obtaining a percentage of the first number with respect to the second number for each of the varied threshold values so as to normalize a density of the input image, and determining the optimum threshold value for binarization based on the percentage which is obtained for each of the varied threshold values.

Abstract: A binarization method obtains an optimum threshold value for binarization which is used when converting a multi-level image data which describes an input image into a black-and-white bi-level image data. The binarization method includes the steps of counting a first number of black picture elements by varying a threshold value from a darkest tone level to a lightest tone level, counting a second number of picture elements having a tone level other than the lightest tone level, obtaining a percentage of the first number with respect to the second number for each of the varied threshold values so as to normalize a density of the input image, and determining the optimum threshold value for binarization based on the percentage which is obtained for each of the varied threshold values.

Abstract: A method for identifying a table region within an input image data of an original obtained by an optical character reader. The table region identification method comprises the steps of extracting first sets of runs of successive black picture elements from each of the lines of the input image data, unifying adjacent runs among the first sets of the runs into first rectangles, unifying second sets of runs within a second rectangle having a size greater than a prescribed size among the thus unified first rectangles to extract ruled lines, the second sets of the runs having a length greater than a prescribed length, and finally making a decision on whether the second rectangle constitutes a table region or any other region depending on the number of the ruled lines counted.

Abstract: A character recognition method includes reading a document having characters displayed thereon and entering a document data representative of the content of the document. Image data of one of the characters from the document data is extracted. The one character has an orientation rotated by an arbitrary rotation angle from a predefined reference position for the one character. A first feature quantity of the one character is extracted from the extracted image data. The extracted feature quantity is converted into a second feature quantity of the one character in the reference position based on the arbitrary rotation angle. A dictionary which contains stored feature quantities of a plurality of characters in the reference position is interrogated so as to find a primary candidate character which has a feature quantity matching or most closely resembling the converted feature quantity.