Steganography and watermarking on BMP images

摘要

In this work we perform some tests of steganography and watermarking on BMP images. We use the Discrete Cosine Transform (DCT) and Wavelets in order to insert information into high and medium frequencies. When steganography is used, we explain a method how to introduce secret data into an image and we show the capacity of the image to accept these data. For the watermarking technique we indicate where the data should be placed in order to achieve a robust insertion of the data even in the presence of image compression. Finally, we make a comparison between these two techniques.