Marcas d'Água Frágeis de Autenticação para Imagens em Tonalidade Contínua e Esteganografia para Imagens Binárias e Meio-Tom

Watermark is an information-carrying signal embedded into digital data that can be extracted later to make some assertion about the data. Digital watermarks are usually classified as robust or fragile. Robust watermarks are designed to resist most image manipulating procedures and are used normally to attest the image ownership. Fragile watermarks are easily corrupted by any image processing procedure. However, integrity checking watermarks must be fragile, in order to detect any alteration. This tutorial course expounds principal authentication watermarking techniques for still continuous-tone images. It also expounds major attacks against these techniques and how to defend against them. Afterwards, this tutorial will describe major techniques to embed data into binary images. We will restrict our study to non-compressed images only.