A reversible watermarking program transforms a host data file into a logical storage unit for auxiliary data files by embedding the auxiliary files in the data stored in the host data file. The reversible watermark modifies host data such as an image, audio, video, or software code, to carry auxiliary data. For perceptual content such as visual or audio media, the reversible watermark can maintain a desired level of perceptual quality, effectively hiding the auxiliary data in the host data. The reversible watermark enables the original host data prior to modifications due to the embedding to be restored.