In this paper, we consider an item authentication using unclonable forensic features of item surface microstructure images (a.k.a. fingerprints). The advocated authentication approach is based on the source coding jointly with the random projections. The source coding ensures the source reconstruction at the decoder based on the authentication data. The random projections are used to cope with the security, privacy, robustness and complexity issues. Finally, the authentication is accomplished as a binary hypothesis testing for both direct and random projections domains. The asymptotic performance approximation is derived and compared with the exact solutions.© (2009) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.