Abstract: Disclosed is a method for determining optimum color gradation levels used by a color gradation barcode in a system including a rendering device for rendering the barcode and a detector for detecting the barcode. The method includes: (a) obtaining input color gradation data; (b) rendering, by using the rendering device, a test pattern based on the input color gradation data, the test pattern comprising at least one color gradation pattern; (c) detecting, by using the detector, the rendered test pattern to generate detected color gradation data; (d) based on the detected color gradation data and the input color gradation data, determining a plurality of optimum color gradation levels to be used for a color gradation barcode; and (e) storing the plurality of optimum color gradation levels.

Abstract: A method of authenticating a document, typically a printed document, is disclosed. The method comprises: (a) processing a first area of a source document according to a first authentication level to generate first authentication data; (b) processing a second area of the source document according to a second authentication level to generate second authentication data, the second authentication level being different from the first authentication level; (c) generating barcode data representing at least the first and second authentication data; and (d) carrying out at least one of: (d1) embedding the barcode data to the source document to generate a processed document; and (d2) printing the barcode data on a recording medium.

Abstract: Disclosed is a method for determining optimum noise filter setting to be used by a scanner in a system including a printer and a detector forming a closed loop system. A test image including a plurality of horizontal lines, vertical lines, slanted lines and dots are printed using the printer and scanned back using the scanner. The scanned test image data is compared to the input test image data representing the test image, and based on such comparison, the optimum noise filter setting for the printer/scanner pair is determined and stored for future use. This method is particularly useful for printing barcodes having high data capacity.

Abstract: A method is described in which metadata regarding a document is encoded as 2d barcode printed on the same recording medium as the document, where the metadata includes an access history of the document and other information. When a printed document including such barcode is copied, the copy includes new barcode containing updated metadata that replaces the original barcode, where the updated metadata includes a record of the current copying or scanning action. When a printed document including such barcode is scanned, the metadata contained in the barcode is extracted and stored. Also described is a document management system including a server connected to one or more clients, scanners, printers, and a storage device for storing documents and metadata. The server includes a digital stamp engine that generates barcode data representing metadata, and supports a variety of workflows including print, barcode generation, scan, copy, barcode update, etc.

Abstract: A document is printed on a recoding medium together with a high resolution 2d barcode that encodes desired information about the document, and a low resolution 2d barcode that encode resolution data that specifies the spatial resolution of the high resolution barcode. The low resolution barcode has a sufficiently low spatial resolution so that it can be adequately read by a majority of scanners at their low resolution settings. Thus, if the printed document is scanned at a low scan resolution, the low resolution barcode can be adequately read to extract the resolution data in order to determined whether the scan resolution is adequate for reading the high resolution barcode. If necessary, the printed document can be re-scanned at a higher scan resolution so that the high resolution barcode can be adequately read. Alternatively, the resolution data may specify the print resolution at which the document is printed.

Abstract: A two-dimensional color barcode using gradations of color is disclosed. The barcode includes a black and white configuration block that encodes configuration information about the barcode and a plurality of color data blocks that encodes data. Each tile in the data blocks has one of the-predefined recoverable gradation values of the RGB, CMY or other color sets. The number of recoverable gradation values for each color used in the color data block is specified in the configuration block. The barcode also includes a corner marker consist of a column and a row of black abutting the configuration block which is located in the top left corner, three additional corner markers and a plurality of block separators along the sides of barcode. Also described are methods for generating and decoding such a 2d color barcode. The methods include transforming data values to be encoded into the color space and vise versa.

Abstract: A two-dimensional color barcode using gradations of color is disclosed. The barcode includes a black and white configuration block that encodes configuration information about the barcode and a plurality of color data blocks that encodes data. Each tile in the data blocks has one of the-predefined recoverable gradation values of the RGB, CMY or other color sets. The number of recoverable gradation values for each color used in the color data block is specified in the configuration block. The barcode also includes a corner marker consist of a column and a row of black abutting the configuration block which is located in the top left corner, three additional corner markers and a plurality of block separators along the sides of barcode. Also described are methods for generating and decoding such a 2d color barcode. The methods include transforming data values to be encoded into the color space and vise versa.

Abstract: A method of authenticating a document, typically a printed document, is disclosed. The method comprises: (a) processing a first area of a source document according to a first authentication level to generate first authentication data; (b) processing a second area of the source document according to a second authentication level to generate second authentication data, the second authentication level being different from the first authentication level; (c) generating barcode data representing at least the first and second authentication data; and (d) carrying out at least one of: (d1) embedding the barcode data to the source document to generate a processed document; and (d2) printing the barcode data on a recording medium.

Abstract: Disclosed is a method for determining optimum color gradation levels used by a color gradation barcode in a system including a rendering device for rendering the barcode and a detector for detecting the barcode. The method includes: (a) obtaining input color gradation data; (b) rendering, by using the rendering device, a test pattern based on the input color gradation data, the test pattern comprising at least one color gradation pattern; (c) detecting, by using the detector, the rendered test pattern to generate detected color gradation data; (d) based on the detected color gradation data and the input color gradation data, determining a plurality of optimum color gradation levels to be used for a color gradation barcode; and (e) storing the plurality of optimum color gradation levels.

Abstract: Disclosed is a method for determining optimum noise filter setting to be used by a scanner in a system including a printer and a detector forming a closed loop system. A test image including a plurality of horizontal lines, vertical lines, slanted lines and dots are printed using the printer and scanned back using the scanner. The scanned test image data is compared to the input test image data representing the test image, and based on such comparison, the optimum noise filter setting for the printer/scanner pair is determined and stored for future use. This method is particularly useful for printing barcodes having high data capacity.

Abstract: A document is printed on a recoding medium together with a high resolution 2d barcode that encodes desired information about the document, and a low resolution 2d barcode that encode resolution data that specifies the spatial resolution of the high resolution barcode. The low resolution barcode has a sufficiently low spatial resolution so that it can be adequately read by a majority of scanners at their low resolution settings. Thus, if the printed document is scanned at a low scan resolution, the low resolution barcode can be adequately read to extract the resolution data in order to determined whether the scan resolution is adequate for reading the high resolution barcode. If necessary, the printed document can be re-scanned at a higher scan resolution so that the high resolution barcode can be adequately read. Alternatively, the resolution data may specify the print resolution at which the document is printed.

Abstract: A method of processing a document is described in which selected area(s) of the document, such as areas containing sensitive information, with a barcode(s) that represents the information in the selected area(s). Selection of the area(s) may be done by a user or automatically. When the processed document is printed or electronically displayed, the selected area(s) is replaced with barcode(s) so the information in the area(s) cannot be visually discerned by a human observer. The intended recipient or reader of the document can decode it using a decoder to display the document, including the selected area(s), in the original form. The method may be implemented in a computer, a scanner/copier, a printer or the like.

Abstract: A method is described in which metadata regarding a document is encoded as 2d barcode printed on the same recording medium as the document, where the metadata includes an access history of the document and other information. When a printed document including such barcode is copied, the copy includes new barcode containing updated metadata that replaces the original barcode, where the updated metadata includes a record of the current copying or scanning action. When a printed document including such barcode is scanned, the metadata contained in the barcode is extracted and stored. Also described is a document management system including a server connected to one or more clients, scanners, printers, and a storage device for storing documents and metadata. The server includes a digital stamp engine that generates barcode data representing metadata, and supports a variety of workflows including print, barcode generation, scan, copy, barcode update, etc.