A watermarking system uses two distinct bit patterns to identify three distinct bits, a logic 0 bit, a logic 1 bit, and a marker bit that demarcates message block boundaries. A correct orientation is determining by rotating the input image by 90 degrees and determining which orientation renders the greatest...http://www.google.de/patents/US8144925?utm_source=gb-gplus-sharePatent US8144925 - Mapping based message encoding for fast reliable visible watermarking
