The newly adopted MPEG-4 Fine Granularity

Scalability (FGS) video coding standard offers full scalability to

enable easy and flexible adaptation to changing constraints and

different requirements. Encryption of an FGS stream should

preserve the full scalability. In this paper, we propose a novel

and low complexity scheme to encrypt MPEG-4 FGS streams

which enables full FGS functionalities. The encrypted FGS

stream can be processed by middle stages directly on the

ciphertext without decryption. In addition, the proposed scheme

has no degradation on either FGS compression efficiency or

error resilient performance, and allows random access.

Experimental results as well as a preliminary security analysis of

the proposed scheme are also included in this paper.