Abstract: An information hiding system that hides information-data in the printing-data according to steganography using an embedding means, and produces printed matter by printing out the printing-data on printable media. A scanner is used to read the data, such as image or pattern data, from the printed matter in order to restore the printing-data. The hidden information-data is then extracted from the restored printing-data using an information-data extracting means. Finally, the information-data is outputted in such a form as an image, musical or voice sound, and/or character letters according to the outputting means.

Abstract: An information card and card system that eliminates forgery and illegal use of a card. The information card includes a memory that stores information data, which includes one of image data and acoustic data and contains inherent data that is embedded in the information data according to steganographic information hiding. The inherent data is data that authenticates a legitimacy of a card owner of the information card. The information card system include the information card and a data processing terminal for authenticating the owner of the card and/or the authenticity of the card itself.

Abstract: A method and computer program product for embedding information within an indexed color image such that the existence of the data is not recognizable by the human eye. The method includes the steps of altering color image data, such that it will not cause a large color change in the representing image, and hiding information using an information hiding method. The altering step is accomplished via a color set changing method. The color set changing method involves first decomposing the image in to a set of color component images, embedding data in the color component or components, which the human visual system is most sensitive to, then merging representative colors until the number of representative colors is less than or equal to the target number of colors and reformatting the resulting image into indexed color image format.

Abstract: A technique for hiding information in an image that is based a property of the human vision system. Because of its relation to human vision properties, the technique of the present invention provides an information hiding capacity is as large as 50% of the original image data. The method includes the steps of segmenting each region of a vessel image into informative and noise-like regions by using a threshold value, arranging the data into a series of data blocks, and embedding each data block into the noise-like regions of the image.

Abstract: An information hiding system that hides information-data in the printing-data according to steganography using an embedding means, and produces printed matter by printing out the printing-data on printable media. A scanner is used to read the data, such as image or pattern data, from the printed matter in order to restore the printing-data. The hidden information-data is then extracted from the restored printing-data using an information-data extracting means. Finally, the information-data is outputted in such a form as an image, musical or voice sound, and/or character letters according to the outputting means.