Cifragem de Imagens Baseada na Transformada Fracional de Fourier sobre Corpos Finitos

The fractional Fourier transform over finite fields (GFrFT) based on the matrix function approach is used to design an image encryption scheme. The approach is simpler than the approach based on the construction of an eigenvector set, therefore allowing lower-cost computation systems. The scheme is a secret-key block cipher, that uses a confusion-diffusion architecture and the GFrFT for image encryption. Computer simulations are performed in order to analyze security aspects. A theoretical analysis and security metrics are used to evaluate the scheme security.