A Survey on Sharing Secret Image using NVSS Scheme

Secret sharing is of great importance for sharing secret or confidential information. This information can be in the form of documents, images, photographs and many more. Most of the previous visual secret sharing scheme uses shares to conceal secret images. The shares may be printed or in digital form. When the secret image is hidden into the shares, noise-like pixel appears which increase the risk of transmission. Attackers look at image having noise-like pixels with suspicion and try to intercept the image. Thus image having noise is not safe for transmission over network. Due to this transmission risk is involved in visual secret sharing. In order to overcome such problems some authors have presented another scheme known as Natural image based Visual Secret Sharing Scheme (NVSS Scheme). In this scheme the transmission of secret image occurs through different media in order to protect the secret. The n out of n NVSS scheme can transmit a digital secret image by randomly choosing n-1 natural images and one noise share. Natural images may be in digital or printed form. Noise-like share is produced by natural image and printed image. The natural shares which are unaltered minimize the risk associated during transmission.