Spread spectrum-based fragile software watermarking

A Spread Spectrum-based fragile software watermarking scheme is proposed in this paper. The algorithm extracts a vector of instruction-group frequencies from all basic blocks of original program and constructs a vector matrix. Furthermore, the scheme generates watermark based on the principal component analysis (PCA) technique and modifies the vector matrix to embed the watermark. With the system, spreading the watermark over the code provides not only a high level of stealth but also a global protection for the original program. The scheme not only can effectively detect tampering, but also has the ability to identify the type of tampering clearly.