Multiple Signature Embedding using Consecutive Pixel Distribution

The widespread use of Internet in conjunction with the appearance of powerful and cheap hardware makes the massive reproduction and distribution of digital material easier than ever before. The digital material is vulnerable to unauthorized modification, duplication and distribution every day. A digitally embedded signature is an identifying characteristic of a picture, audio, video, or any other piece of digital media. We present a method for embedding multiple signatures in an image using its consecutive pixel distribution. Exploiting the HVS (Human Vision System), the digital signature is embedded in the blue channel of a RGB image. The method consists of a set of scan patterns, which produce different scan orders for pixels of each digital image. The distribution of the consecutive bit-streams is first calculated. Then, a specific a bitsequence is selected, and is used as a marker of the beginning of the signature. A m-bit signature is embedded after each appearance of the chosen bit-sequence at the blue channel. This mechanism is accompanied by a key. This key is composed of the bit-sequence, the scanning method and the m-bit signature. With the aid of the key, the parsing method can be applied, in order to recover the signature and certify the owner of a digital image. Each time the chosen bit-sequence is detected, the m-bits that follow it are extracted. Every extracted m-bit stream is XORed with the original m-bit signature, and the results are stored in a repository. The reliability of the restored signature depends on the fraction of zeros that appear in the end of the above process in the repository. The higher the number of zeros the more reliable the signature is.