Multimedia Transcoding in Mobile and Wireless Networks

Secure multimedia transcoding is a challenge that operates the encrypted multimedia content directly. For example, the encrypted multimedia data’s bit rate is changed directly in order to adapt a narrow channel. However, since it avoids the triple operations decryption-transcoding-re-encryption, it is suitable for the application scenarios requiring low cost operations, such as wireless or mobile multimedia communication. In this chapter, the secure transcoding scheme for scalable video coding is proposed and analyzed, together with the introduction to scalable video coding and multimedia encryption, the overview of existing secure transcoding schemes, and some open issues in this field. The chapter is expected to provide researchers or engineers valuable information on secure multimedia transcoding and communication.