Visual cryptography is one of the techniques used to encrypt the images by dividing the original image into transparencies. The transparencies can be sent to the intended person, and at the other end the transparencies received person can decrypt the transparencies using our tool, thus gets the original image. In this paper is to resolve the problem of visual secret sharing for general access structures using the concept of visual cryptograms of random grids (VCRG). The visual secret sharing schemes, which are an interesting visual variant of the ordinary secret sharing schemes. There is a secret picture to be shared among n participants.
The picture is divided into n transparencies (shares) such that if any m transparencies are placed together, the picture becomes visible, but if fewer than m transparencies are placed together, nothing can be seen. Such a scheme is constructed by viewing the secret picture as a set of black and white pixels and handling each pixel separately. A further improvement allows each transparency
(share) to be an innocent picture (e.g. a picture of a landscape or a picture of a building), thus concealing the fact that secret sharing is taking place.
The proposed Visual Cryptograms of Random Grids (VCRG-GAS) algorithms require no extra pixel expansion and can be extended to cope with color images.
The contribution of VCRG on reducing the pixel expansion is significant from either theoretical or practical perspectives. proposed recently, including probabilistic VCS, multipixel encoding or random grids.

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Data security has been a challenging task in visual cryptography system and database systems.
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The existing visual cryptography schemes that are used for data hiding have a security hole in the encrypted Share file.
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Each participant holds a transparency. Most of the previous research work on VC’s focuses on two parameters: large pixel expansion and contrast.
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The pixel expansion and relative contrast are the most critical measurements to evaluate the effectiveness of a VCS.
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The existing system does not provide a friendly environment to encrypt or decrypt the data (images).
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The existing system supports with only one type of image format only. For example, if it is .jpg, then it supports only that same kind of image format only.

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This project concentrates on the task to provide security features for database system in terms of visual Secret sharing schemes.
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First, an image is split into n encrypted shares using Pixel expansion, share alignment algorithm by the fact that a pixel can be split into sub pixels.
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We have in order to avoid hacking of shared image; we employ password protection for each share using Pixel expansion, share alignment algorithm.
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Then, we perform rearranging of pixels of shared image by overlaying process to obtain the access to the protected secret image.
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Secret Image has been compressed, and then it embedded using the proposed Visual Cryptograms of Random Grids (VCRG-GAS)scheme.
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There is a secret image quality can be measured by the average contrast.

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Platform : JAVA (JDK 1.5)
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Front End : JAVA Swing
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IDE : NETBEANS 6.9
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Operating System : Microsoft Windows 2000 or XP
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Processor
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RAM
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Monitor
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Keyboard
: Pentium IV Processor
: 512 MB
: 14” VGA COLOR MONITOR
: 104 Keys