Abstract
In this thesis, two types of embedding techniques are proposed. One is that of embedding secret data into condensed images while and the other applies to multiple images. Many steganographic techniques are currently exploited for the VQ index table. However, the embedding strategies require longer compression codes and decrease visual quality. Secret-sharing is a technique first invented by Shamir. It is used to split a secret into n shares and then distribute them to n users. Later, t shares can cooperate to reconstruct the secret, called the (t,n)-threshold. Recently, many meaningful secret sharing schemes have yielded authentication mechanisms, yet none included a remedy ability, which may mean that the secret image will not be obtained completely, while some information about stego images is lost. In the first method, we tried to satisfy the essentials of increasing the secret payload, preserve the VQ index table without loss, and reduce the compression rate. The proposed scheme utilizes search order coding to determine the correlation between the VQ indices and neighboring indices. Because of the similarity among adjacent indices, the new method can embed the secret bits into the index table and encode the embedded index table using fewer bits. In the second method, we proposed a meaningful secret sharing scheme to include the authentication and remedy abilities that allow for some data loss in the secret image. This approach has the ability to repair the secret image with reasonable visual quality.