Abstract: In verification of image data of a captured image as to whether it is original one, the verification is possible even for image data subjected to a peripheral illumination correction or an exposure correction. An order information calculation unit selects a pixel set including two or more pixels based on pixel values and information on an image space of image data of a captured image, and calculates an order of magnitude between pixels in the selected pixel set. A verification data producing unit generates verification data used in verification of whether the image data has not been tampered with, based on the calculated order of magnitude. An image output unit outputs the image data and the verification data.

Abstract: An information embedding apparatus (100) which embeds information by changing the character spacing in a document image includes a discrimination unit (101) which discriminates a text area in the document image, a circumscribed rectangle extraction unit (102) which extracts the circumscribed rectangle of each character in the text area, a determination unit (103) which determines, based on the position and size of each extracted circumscribed rectangle, whether a portion having a character spacing smaller than a threshold exists, a reduction unit (104) which, for a character determined to have a character spacing smaller than the threshold, reduces the size of the character in at least the character arrangement direction, and a character position changing unit (105) which changes, in accordance with information to be embedded, the position of a character determined to have a character spacing equal to or larger than the threshold, and that of a character reduced.

Abstract: In verification of image data of a captured image as to whether it is original one, the verification is possible even for image data subjected to a peripheral illumination correction or an exposure correction. An order information calculation unit selects a pixel set including two or more pixels based on pixel values and information on an image space of image data of a captured image, and calculates an order of magnitude between pixels in the selected pixel set. A verification data producing unit generates verification data used in verification of whether the image data has not been tampered with, based on the calculated order of magnitude. An image output unit outputs the image data and the verification data.

Abstract: A predetermined region set on a grayscale image is divided into rectangles each having a predetermined size (S706), and piled patterns which hold the accumulated values of pixel values at identical pixel positions upon piling up the divided rectangles is generated (S707). An alignment pattern is generated by calculating the logical sum of respective bit expression patterns (S708). A peak position which matches the alignment pattern on the piled patterns best is obtained (S710). The position of the predetermined region is corrected based on the peak position, and the predetermined region after correction is divided into rectangles each having the predetermined size (S711) Patterns in the divided rectangles are recognized (S712). Embedding information corresponding to each recognized pattern is specified (S713).

Abstract: A copy-forgery-inhibited pattern image including added digital information is generated by an on-demand output of the pattern by a printer. An image processing apparatus for generating a copy-forgery-inhibited pattern image includes: a pattern storage section for storing a plurality of patterns that constitute a camouflage pattern image and that respectively represent specific bit values; an information input unit for inputting arbitrary information; and a camouflage pattern image structuring unit for receiving the information from the information input unit to represent a bit string of a binary representation of the information as an arrangement of a plurality of patterns. The image processing apparatus further includes a random number generation unit for generating a random number sequence; and a selection output unit for receiving the random number sequence from the unit and the information outputted from the information input unit to output, based on predetermined information, any one of them.

Abstract: It is required to protect the copyrights and the like of partial images which form respective parts of an image obtained by reading an image, exchanged using a print as a medium, by an image scanner or the like. Input image data is divided into a plurality of image regions having different features, digital watermarks, which are embedded in the detected image regions by embedding methods corresponding to the features of the image regions, are extracted, and the availability of the input image is checked on the basis of the extracted digital watermarks.

Abstract: An information embedding apparatus (100) which embeds information by changing the character spacing in a document image includes a discrimination unit (101) which discriminates a text area in the document image, a circumscribed rectangle extraction unit (102) which extracts the circumscribed rectangle of each character in the text area, a determination unit (103) which determines, based on the position and size of each extracted circumscribed rectangle, whether a portion having a character spacing smaller than a threshold exists, a reduction unit (104) which, for a character determined to have a character spacing smaller than the threshold, reduces the size of the character in at least the character arrangement direction, and a character position changing unit (105) which changes, in accordance with information to be embedded, the position of a character determined to have a character spacing equal to or larger than the threshold, and that of a character reduced.

Abstract: An apparatus for embedding a digital watermark in a document image detects circumscribing outer shapes of characters in the document image and sets a plurality of reference lines that extend in the column direction and are spaced apart in the row direction by a basic pitch. The outer shapes include a first outer shape, a second outer shape that neighbors the first outer shape, and a third outer shape that neighbors the second outer shape, and the reference lines include a first reference line located between the first outer shape and the second outer shape, and a second reference line located between the second outer shape and the third outer shape. Control is performed for at least one of the second and third outer shapes so that a distance between the first reference line and an edge of the second outer shape is different from a distance between the second reference line and an edge of the third outer shape, in accordance with digital watermark information to be embedded.

Abstract: Distance d1 between the right edges of A1 and B2, and distance d2 between the right edges of A3 and B4 are calculated. If data to be embedded is 1, one or a combination of a process for increasing the size of B2 in the column direction or decreasing the size of B4 in the column and a process for moving the position of B2 toward B3 or moving the position of B4 toward B3 is executed to meet d1>d2. If data to be embedded is 0, one or a combination of a process for decreasing the size of B2 in the column direction or increasing the size of B4 in the column direction, and a process for moving the position of B2 toward B1 or moving the position of B4 toward B5 is executed to meet d1<d2.

Abstract: A predetermined region set on a grayscale image is divided into rectangles each having a predetermined size (S706), and piled patterns which hold the accumulated values of pixel values at identical pixel positions upon piling up the divided rectangles is generated (S707). An alignment pattern is generated by calculating the logical sum of respective bit expression patterns (S708). A peak position which matches the alignment pattern on the piled patterns best is obtained (S710). The position of the predetermined region is corrected based on the peak position, and the predetermined region after correction is divided into rectangles each having the predetermined size (S711) Patterns in the divided rectangles are recognized (S712). Embedding information corresponding to each recognized pattern is specified (S713).

Abstract: It is required to protect the copyrights and the like of partial images which form respective parts of an image obtained by reading an image, exchanged using a print as a medium, by an image scanner or the like. Input image data is divided into a plurality of image regions having different features, digital watermarks, which are embedded in the detected image regions by embedding methods corresponding to the features of the image regions, are extracted, and the availability of the input image is checked on the basis of the extracted digital watermarks.

Abstract: A document image undergoes document analysis to obtain circumscribing rectangles of characters (S601), and two distances between non-neighboring circumscribing rectangles from the head of the document are respectively calculated as d1 and d2 (S603). If information to be embedded is 1, one or a combination of a process for changing a parameter associated with the size of a circumscribing rectangle and a process for changing a parameter associated with the position of a circumscribing rectangle is executed to satisfy d1>d2 (S605). If information to be embedded is 0, one or a combination of the above two parameter change processes is executed to satisfy d1<d2 (S606).

Abstract: The invention is to precisely extract a digital watermark from image data which are subjected to embedding of the digital watermark in a state of a binary image and are then converted into a multi-value image (gray scale image). For attaining the foregoing object, a digital watermark extracting apparatus for extracting a digital watermark for example in an original includes an acquiring unit for acquiring multi-value image data obtained by reading the original with a predetermined reading unit, a pre-processing unit for selecting one of plural threshold values and binarizing the multi-value image data with the selected threshold value, and an extracting unit for extracting the digital watermark from image data binarized in the pre-processing unit, wherein selection of the threshold value, binarization an extraction of the digital watermark are repeated to obtain an optimum extraction result of the digital watermark.

Abstract: A copy-forgery-inhibited pattern image including added digital information is generated by an on-demand output of the pattern by a printer. An image processing apparatus for generating a copy-forgery-inhibited pattern image includes: a pattern storage section for storing a plurality of patterns that constitute a camouflage pattern image and that respectively represent specific bit values; an information input unit for inputting arbitrary information; and a camouflage pattern image structuring unit for receiving the information from the information input unit to represent a bit string of a binary representation of the information as an arrangement of a plurality of patterns. The image processing apparatus further includes a random number generation unit for generating a random number sequence; and a selection output unit for receiving the random number sequence from the unit and the information outputted from the information input unit to output, based on predetermined information, any one of them.

Abstract: This invention provides a digital watermark embedding apparatus for a document, which can eliminate unnaturalness that may be experienced upon laying out characters in a document when watermark information is embedded, while maintaining the robustness of a document itself and the information size to be embedded of a digital watermark. A document image is input from an image input unit (11), and watermark information is input from a watermark information input unit (15). A region division unit (12) divides the document image into regions, and a circumscribing rectangle extraction unit (13) sets circumscribing rectangles for characters and extracts them as character images. A punctuation mark determination unit (14) determines a punctuation mark from the character image. A watermark information embedding unit (16) embeds watermark information by digital watermarking that shifts character images other than the character image determined to be a punctuation mark.

Abstract: Distance d1 between the right edges of A1 and B2, and distance d2 between the right edges of A3 and B4 are calculated. If data to be embedded is 1, one or a combination of a process for increasing the size of B2 in the column direction or decreasing the size of B4 in the column and a process for moving the position of B2 toward B3 or moving the position of B4 toward B3 is executed to meet d1>d2. If data to be embedded is 0, one or a combination of a process for decreasing the size of B2 in the column direction or increasing the size of B4 in the column direction, and a process for moving the position of B2 toward B1 or moving the position of B4 toward B5 is executed to meet d1<d2.

Abstract: Circumscribing rectangles of respective characters in a document image are obtained. In a first pair as a pair of a first circumscribing rectangle in a first line (a line of A1 to A7) serving as a reference line, and a second circumscribing rectangle in a second line (a line of B1 to B4 or C1 to C7) as one of lines other than the reference line, and a second pair as a pair of a third circumscribing rectangle in the first line, and a fourth circumscribing rectangle in the second line, of these circumscribing rectangles, at least one of the circumscribing rectangles included in these pairs is controlled to vary the distance between the circumscribing rectangles of the first pair, and the distance between the circumscribing rectangles of the second pair in accordance with digital watermark information to be embedded, thereby embedding the digital watermark information.

Abstract: The invention is to precisely extract a digital watermark from image data which are subjected to embedding of the digital watermark in a state of a binary image and are then converted into a multi-value image (gray scale image).

Abstract: A document image undergoes document analysis to obtain circumscribing rectangles of characters (S601), and two distances between non-neighboring circumscribing rectangles from the head of the document are respectively calculated as d1 and d2 (S603). If information to be embedded is 1, one or a combination of a process for changing a parameter associated with the size of a circumscribing rectangle and a process for changing a parameter associated with the position of a circumscribing rectangle is executed to satisfy d1>d2 (S605). If information to be embedded is 0, one or a combination of the above two parameter change processes is executed to satisfy d1<d2 (S606).

Abstract: It is required to protect the copyrights and the like of partial images which form respective parts of an image obtained by reading an image, exchanged using a print as a medium, by an image scanner or the like. Input image data is divided into a plurality of image regions having different features, digital watermarks, which are embedded in the detected image regions by embedding methods corresponding to the features of the image regions, are extracted, and the availability of the input image is checked on the basis of the extracted digital watermarks.