Abstract:
Disclosed is a preprinting system of secured information connected to a game host device. The preprinting system includes a controller, a printer, a plurality of printer detectors, a housing, a plurality of housing detectors. The controller is configured to communicate with the game host device, and to receive a game information signal and a status checking request signal. The printer is electronically connected to the controller, which is configured to print a game draw of the game program on printable medium, and the printed printable medium is partially revealed to the player while the game result draw thereon is unknown to the player. By preprint game draw of the game program, the possibility of adulteration from the game system is eliminated, the preprinting system also provides reliability, and the verification mechanism provides information security of digital chance games to the players. An preprinting method of secured information is also disclosed.
Abstract:
The present invention provides systems and methods for digital content security. In one embodiment, a method includes generating an input key, generation of the input key comprising a sequence of operations, the operations including: performing at least one circular-bit-shift operation on a gradient image, and performing at least one block-wise permutation on the gradient image. One such method further includes performing a fragile watermark-embedding algorithm using the input key. Another such method includes utilizing the input key for encryption.
Abstract:
Techniques for secure distribution of digital representations that combine encryption and watermarking. When a user at a client desires to download a digital representation, the user makes a request to a server for the digital representation, which encrypts the digital representation using a first key and downloads the encrypted digital representation to the user. Before the user performs any operation on the decrypted digital representation, a secret fingerprint watermark identifying the user is added to the digital representation. The fingerprint watermark is added either at the server or at the client and a copy of the fingerprinted digital representation is kept at the server. If the user makes an impermissible use of the digital representation, the secret fingerprint watermark can be used to identify the user. The request made by the user indicates the type of use that the user whished to make of the digital representation. If the use involves storage of the digital representation at the client, the server provides a second key that the client employs to encrypt the digital representation. If the user has permission to do so, the user may modify the digital representation and return the modified digital representation to the server for further distribution. In this case, the second key is used to encrypt the digital representation when it is sent to the server. The second key also serves as the user identification in the fingerprint watermark. If the user loses the second key, it can be recovered from the copy of the fingerprinted digital representation kept at the server. The first and second keys and any decrypted copy of the digital representation are kept in secure storage in the client.
Abstract:
A method and apparatus are described for inserting a watermark in the compressed domain. The watermark inserted does not require a reference. An overall watermarking system incorporating the invention combines cleartext, bitstream, and integrated watermarking. In a perceptual coder, the data enters a filterbank, where it is processed into multiple separate coefficients. A rate/distortion control module uses noise threshold information from a perceptual coder, together with bit-count information from a noiseless coder, to compute scale factors. The coefficients are multiplied by the scale factors and quantized, then noiseless coded and then output for further processing/transmission. The invention supports three embodiments for inserting a mark into the bitstream imperceptibly. It is assumed that some set of scale factor bands have been selected, into which mark data will be inserted. In one embodiment, a set of multipliers {xi=2 : i ELEMENT M} is chosen. Each triple is modified by dividing the scale factor by xi, multiplying the quantized coefficients by {xi}, and adding mark data to the non-zero modified quantized coefficients. In an alternate embodiment, watermark data is represented via two characteristics of the bitstream data. A Huffman table is selected for encoding the Scale Factor Band receiving watermark data which is not the table that would normally be used. The watermark data bit is set according to any desired scheme, and the quantized coefficients are derived using the alternate Huffman table. In another embodiment, watermarking is integrated with quantization. The watermark is therefore difficult to remove without perceptible effects. The fact that marking data is present is again indicated by characteristics of the bitstream data. The modification factors {xi} are now all close to unity.
Abstract:
Ce procédé de tatouage de livres numériques avec des paramètres comporte : - l'élaboration (56) pour chaque paramètre d'une nouvelle police de caractères à partir d'une police préexistante, en créant au moins une nouvelle paire code-glyphe, - l'élaboration (58) d'un nouveau texte codé à partir du texte préexistant codé en remplaçant dans le texte préexistant codé au moins un code ou groupe de codes de la police préexistante permettant d'afficher un caractère ou une combinaison de caractères du livre numérique par le code ou le groupe de codes de la nouvelle police permettant d'afficher le caractère ou la combinaison de caractères graphiquement identique sur un écran quelconque, ce code ou ce groupe de codes de la nouvelle police comportant au moins le code de la nouvelle paire code-glyphe, - la fourniture (64) en tant que livre numérique tatoué du nouveau texte codé et de la nouvelle police.
Abstract:
A method of protecting digital image, the method comprising extracting feature values from the digital image based on a selected authentication bit-rate; embedding data corresponding to the feature values as a watermark in a into the digital image; and creating an image signature based on the data corresponding to the feature values.
Abstract:
The content (Ic), which is disseminated to at least one user, is coded for the dissemination thereof. The method comprises a content (Ic) decoding stage and a stage in which the content is marked with the aid of user identification information (Wk), said steps being coupled to each other in such a way that the execution of one step results in the execution of the other step. The content is encrypted with the aid of an encoding key using a secret key (Kst). The method also comprises the following steps: calculation of a mixed key (Kstwk) resulting from the mixing of the secret key (Kst) and user identification (Uk) information (Wk) on a data medium (5); transmission of the mixed key (Kstwk) from the data medium (5) to the decoding and marking device (3); calculation of the secret key (Kst) and user identification information (Wk) on the basis of the mixed key (Kstwk) by the decoding and marking device (3); the secret key (Kst) and user (uk) identification information (Wk) are then used respectively to decrypt and mark the content (Ic).
Abstract:
Le contenu (Ic), diffusé vers au moins un utilisateur, étant codé pour sa diffusion, le procédé comprend une étape de décodage du contenu (Ic) et une étape de marquage du contenu à l'aide d'informations d'identification (W k ) de l'utilisateur couplées l'une à l'autre de telle sorte que l'exécution de l'une entraîne l'exécution de l'autre. Le contenu étant chiffré à l'aide d'un algorithme de chiffrement utilisant une clé secrète (Kst), le procédé comporte en outre les étapes suivantes : calcul d'une "clé mélangée" (Kstw k ) résultant du mélange de la clé secrète (Kst) et des informations d'identification (W k ) de l'utilisateur (U k ), sur un support de données (5), transmission de la "clé mélangée" (Kstw k ) du support de données (5) vers le dispositif de décodage et de marquage (3), calcul de la clé secrète (Kst) et des informations (W k ) d'identification de l'utilisateur à partir de la clé mélangée (Kstw k ), par le dispositif de décodage et de marquage (3), la clé secrète (Kst) et les informations (W k ) d'identification de l'utilisateur (u k ) étant ensuite utilisées pour respectivement déchiffrer le contenu (Ic) et le marquer.
Abstract:
A device (1) for decrypting an encrypted image (B) displayed on a display device (2) has sensor elements (21) for sensing the encrypted image (B) and display elements (22) for displaying the decrypted image (C). The decryption is carried out by electrical or optical connections (13) between the sensor elements (21) and the display elements (22) and may involve a permutation of the image elements. A method of decrypting an encrypted image (B) displayed on a display device (2) involves using a decryption device (1) for carrying out a permutation to produce a decrypted image (C).