Visual secret sharing has received more and more attention over the past years due to the fact that neither complex computation nor cryptographic knowledge is required to decrypt the secret image directly according to...Visual secret sharing has received more and more attention over the past years due to the fact that neither complex computation nor cryptographic knowledge is required to decrypt the secret image directly according to the characteristics of the human vision system. Considering the issue of sharing the secret image at multiple image resolutions with the meaningful shadows, in this paper, we present a friendly progressive visual secret sharing scheme without expanding the image size in the shadows and the reconstructed secret image based on applying a 2x2-sized block-wise operation to generate the shadows block by block. The proposed method can achieve these benefits： 1） the generated shadows are meaningful, and their sizes are not expanded, and 2） the secret image can be recovered at different resolutions by stacking different quantities of shadows together. The experimental results also show that the proposed method is superior to other compared schemes.展开更多
Visual cryptography scheme （VCS） is a secure method that encrypts a secret image by subdividing it into shadow images. Due to the nature of encryption VCS is categorized into two types： the deterministic VCS （DVCS...Visual cryptography scheme （VCS） is a secure method that encrypts a secret image by subdividing it into shadow images. Due to the nature of encryption VCS is categorized into two types： the deterministic VCS （DVCS） and the probabilistie VCS （PVCS）. For the DVCS, we use m （known as the pixel expansion） subpixels to represent a secret pixel. The PVCS uses only one subpixel to represent a secret pixel, while the quality of reconstructed image is degraded. A well-known construction of （k, n）-PVCS is obtained from the （k, n）-DVCS. In this paper, we show another construction of （k, n）-PVCS by extending the （k, k）-PVCS.展开更多
A lossless image secret sharing using a simple Boolean operation is proposed. The concept of visual cryptography in the secret sharing scheme is used to redesign a lossless secret sharing scheme. To ensure that the re...A lossless image secret sharing using a simple Boolean operation is proposed. The concept of visual cryptography in the secret sharing scheme is used to redesign a lossless secret sharing scheme. To ensure that the reconstructed image is the true secret image, an authentication mechanism is imported into the proposed scheme to verify whether the shadows are authentic before reconstructing the secret image. The proposed scheme delivers much more effective performance than Chen and Wu＇s scheme.展开更多
文摘Visual secret sharing has received more and more attention over the past years due to the fact that neither complex computation nor cryptographic knowledge is required to decrypt the secret image directly according to the characteristics of the human vision system. Considering the issue of sharing the secret image at multiple image resolutions with the meaningful shadows, in this paper, we present a friendly progressive visual secret sharing scheme without expanding the image size in the shadows and the reconstructed secret image based on applying a 2x2-sized block-wise operation to generate the shadows block by block. The proposed method can achieve these benefits： 1） the generated shadows are meaningful, and their sizes are not expanded, and 2） the secret image can be recovered at different resolutions by stacking different quantities of shadows together. The experimental results also show that the proposed method is superior to other compared schemes.
基金supported in part by the Testbed@TWISC, National Science Council under the Grant No. 100-2219-E-006-001in part by National Natural Science Foundation of China under the Grant No. 60903210
文摘Visual cryptography scheme （VCS） is a secure method that encrypts a secret image by subdividing it into shadow images. Due to the nature of encryption VCS is categorized into two types： the deterministic VCS （DVCS） and the probabilistie VCS （PVCS）. For the DVCS, we use m （known as the pixel expansion） subpixels to represent a secret pixel. The PVCS uses only one subpixel to represent a secret pixel, while the quality of reconstructed image is degraded. A well-known construction of （k, n）-PVCS is obtained from the （k, n）-DVCS. In this paper, we show another construction of （k, n）-PVCS by extending the （k, k）-PVCS.
基金supported by the National Science Council under Grant No. NSC100-2218-E-468-002-MY2
文摘A lossless image secret sharing using a simple Boolean operation is proposed. The concept of visual cryptography in the secret sharing scheme is used to redesign a lossless secret sharing scheme. To ensure that the reconstructed image is the true secret image, an authentication mechanism is imported into the proposed scheme to verify whether the shadows are authentic before reconstructing the secret image. The proposed scheme delivers much more effective performance than Chen and Wu＇s scheme.
