Abstract: The invention is a novel watermark in a media sequence and systems and methods for embedding and detecting the watermark. Different watermarks from a watermark set of pseudo random watermarks are selected (randomly or by a selection pattern) and each selected watermark is embedded in a different selected I-frame set of the media stream. Identifying the known sequence of watermarks in the stream of I-frames of a copy can identify the video stream from which the copy originates.

Abstract: The invention is a novel watermark in a media sequence and systems and methods for embedding and detecting the watermark. Different watermarks from a watermark set of pseudo random watermarks are selected (randomly or by a selection pattern) and each selected watermark is embedded in a different selected I-frame set of the media stream. Identifying the known sequence of watermarks in the stream of I-frames of a copy can identify the video stream from which the copy originates.

Abstract: The present invention provides methods and apparatus for embedding an identifying pattern of visible speckles into the digitized image of each page of a document. A speckle is a cluster of black or white pixels. Speckles are printed as black speckles on the white paper, or conversely, as areas of missing black removed from the black text characters, called white speckles. The collective pattern of all embedded black and white speckles on a single document page is called a specklemark. A specklemark can survive contrast manipulations on photocopiers and binary rasterization done by fax scanning prior to data transmission. The random pattern of the black and white speckles visible in the digitized image of a document page can be detected automatically, and by systematically matching the detected pattern with those known to have been embedded into marked copies of a document page, a specific document copy can be identified.

Abstract: The present invention provides methods and apparatus for embedding an identifying pattern of visible speckles into the digitized image of each page of a document. A speckle is a cluster of black or white pixels. Speckles are printed as black speckles on the white paper, or conversely, as areas of missing black removed from the black text characters, called white speckles. The collective pattern of all embedded black and white speckles on a single document page is called a specklemark. A specklemark can survive contrast manipulations on photocopiers and binary rasterization done by fax scanning prior to data transmission. The random pattern of the black and white speckles visible in the digitized image of a document page can be detected automatically, and by systematically matching the detected pattern with those known to have been embedded into marked copies of a document page, a specific document copy can be identified.

Abstract: The present invention provides an image watermarking technique whereby a watermark is inserted into an adjusted digital source image that is bounded by a specific bounding rectangle. If the source image is larger than the rectangle, its dimensions are reduced by a common factor until it is the largest adjusted image that lies totally within the rectangle. A watermark is inserted into the adjusted image and at least one derived image of larger or smaller size is produced. Then, regardless of the size of an image derived from the watermarked adjusted image, enlarging or reducing that image to again lie within the rectangle greatly facilitates detection of the imbedded watermark. The size of the bounding rectangle may be specific to each source image, or, conversely, a common bounding rectangle may be used for a group of source images.

Abstract: Pages of books are copied without distortion due to curvature of the page near the book binding or the distortion in a copied page is corrected using the spacing of equidistant bars on tape strips applied to the top and bottom edges of a page before copying. The tape is preferably transparent and rather narrow and easily attached to a page to be copied. The first step in the distortion correction procedure is to locate the bars at the top and bottom of the page. The distortion of the spacing between the imaged bars is computed based on the known distance between the equidistant bars. The computed distortion of the spacing is then input to a distortion correction algorithm. The output of the distortion correction algorithm generates a corrected image. This image may also optionally delete the bars so that they are not printed in the copy. The corrected image is then copied.

Abstract: The present invention provides methods and apparatus for imparting a multiplicity of watermarks onto a digitized image. The image includes a plurality of pixels, wherein each of the pixels includes brightness data that represents one brightness value if the image is monochrome, or a plurality of brightness data values if the image has multiple colors. In one aspect it provides for imparting more than one watermark into the digitized image comprising the steps of providing the digitized image, and multiplying the brightness data associated with at least one of the image pixels by a plurality of predetermined brightness multiplying value. Another aspect of the present invention is to provide a method for generating a composite watermark and imparting on a plurality of copies of a digitized image a different composite watermark into each copy. Also provided is a method for detecting one or more of the watermarks in the composite.

Abstract: Pages of books are copied without distortion due to curvature of the page near the book binding or the distortion in a copied page is corrected using the spacing of equidistant bars on tape strips applied to the top and bottom edges of a page before copying. The tape is preferably transparent and rather narrow and easily attached to a page to be copied. The first step in the distortion correction procedure is to locate the bars at the top and bottom of the page. The distortion of the spacing between the imaged bars is computed based on the known distance between the equidistant bars. The computed distortion of the spacing is then input to a distortion correction algorithm. The output of the distortion correction algorithm generates a corrected image. This image may also optionally delete the bars so that they are not printed in the copy. The corrected image is then copied.

Abstract: A digital watermarking method encodes different pairs of watermarks into each of a plurality of images offered for use by a vendor. The watermarks in each pair are derived from two separate collections of watermarks and sufficiently different so as to prevent false positives. Because each pair of watermarks is assigned to a different customer relative to a particular image, unauthorized use of a digital image sold to a customer may be determined by locating the associated pair of watermarks assigned to the customer in the image. Collusion detection is also realized by forming each pair of masks from sub-collections of masks which are detectable in an image formed by combining the same images sold to one or more customers.

Abstract: The present invention provides methods and apparatus for imparting a multiplicity of watermarks onto a digitized image. The image includes a plurality of pixels, wherein each of the pixels includes brightness data that represents one brightness value if the image is monochrome, or a plurality of brightness data values if the image has multiple colors. In one aspect it provides for imparting more than one watermark into the digitized image comprising the steps of providing the digitized image, and multiplying the brightness data associated with at least one of the image pixels by a plurality of predetermined brightness multiplying value. Another aspect of the present invention is to provide a method for generating a composite watermark and imparting on a plurality of copies of a digitized image a different composite watermark into each copy. Also provided is a method for detecting one or more of the watermarks in the composite.

Abstract: Faithful color images are created in an efficient manner for display on a specific computer display. A standard computer system generates a palette calibration table, based on information about a standard display. The standard computer system then creates a device independent image from the palette calibration table and from an original image. The palette calibration table and device independent image are then transmitted to a specific computer system. The specific computer system receives the palette calibration table and device independent image from the standard computer system. It calculates a display specific palette from the palette calibration table and from information about the specific display. The specific computer system then generates the faithful color image for display by sending the device independent image and the display specific palette to the display adapter in the specific computer system.

Abstract: A system for placing a visible "watermark" on a digital image is disclosed, wherein an image of the watermark is combined with the digital image. The pixels of the watermark image are examined, and for each pixel whose value is not a specified "transparent" value, the corresponding pixel of the original image is modified by changing its brightness but its chromaticities. This results in a visible mark which allows the contents of the image to be viewed clearly, but which discourages unauthorized use of the image.

Abstract: Faithful color images are created in an efficient manner for display on a specific computer display. A standard computer system generates a palette calibration table, based on information about a standard display. The standard computer system then creates a device independent image from the palette calibration table and from an original image. The palette calibration table and device independent image are then transmitted to a specific computer system. The specific computer system receives the palette calibration table and device independent image from the standard computer system. It calculates a display specific palette from the palette calibration table and from information about the specific display. The specific computer system then generates the faithful color image for display by sending the device independent image and the display specific palette to the display adapter in the specific computer system.

Abstract: An inter-processor interrupt mechanism is implemented in a shared-memory multi-processor system. A dedicated halfword for each processor in said multi-processor system is provided in the shared memory restricted in use to the generation and control of inter-processor interrupts. No data in any dedicated shared-memory location can be altered by any processor unless it has "captured" the location by executing a test and set halfword instruction and a captured shared-memory location being released only by executing a store halfword instruction. An address comparator and a zero detector are added as adjunct operations to read-modify-write logic of each processor's memory interface. When any instruction is executed and its operand address agrees with that contained in the address comparator, an inter-processor interrupt request is generated if zero is not detected on all predefined data bits being written to memory.

Abstract: A method for selecting a limited number of presentation colors from a larger palette for a selected image. A three dimensional color histogram of said image is generated and a first color is selected based upon the color occurring most frequently in the image. Subsequent presentation colors are selected by choosing one at a time those colors having the highest weighted frequency of occurrence wherein the weighting is such that colors closest to the previously selected color are weighted very little while colors furthest away from the previously selected color are weighted the most.

Abstract: A system or scheme for automatic detection of and recovery from transmission errors in the asynchronous communication mode at the data link level with complete transparency at the higher levels is disclosed wherein the transmissions are in the form of a sequence of data packets, and an improved combination of end-of-text (ETX) bytes along with checksums is used in each data packet to detect errors. The ETX character is dynamically selected for each packet after the data comprising the packet has been assembled. This character is coded differently from the remaining character codes in its respective packet and is made the second byte thereof following the start-of-text byte (STX). The third byte in each packet is made the complement of the preceding ETX byte, the latter of which is also made the last byte in the packet. Thus, the second and last bytes in each packet are identical, and different from all the other bytes, and the third byte is their complement.