In order to associate information with multimedia content,
one of the straightforward schemes is to stuff information into
reserved fields of digital media file headers. However,
information contained in file headers may get easily lost after
careless file format conversion. To another extreme, auxiliary
information can be directly printed onto visual media in the
form of obvious patterns. Conventionally, these imprinted
patterns are often human-comprehensible texts or logos. Inrecent years, 1-D or 2-D barcodes printed on content surfaces
have become prevalent mechanisms for auxiliary information
delivery. However, inevitable quality degradation often
seriously reduces the commercial values of visual content. In
addition, both approaches are inappropriate for steganography
applications