摘要 |
Data to be impressed upon the average value of a chrominance portion of a block, is replicated at least once. The original and each replica is impress ed on blocks in the same block position of separate frames. The frames that have like- positioned blocks that are carrying the same data are considered to be a group. Specifi c blocks of the frame may be embedded with a particular known data sequence rather th an user data. Each group may employ a different known sequence. Instead of simply repeating the data for each like-positioned block of a group, the amount add ed to the average value for each such block may be changed slightly from frame to fram e in group, even when the complexity of the blocks is the same. At a receiver, th e multiple instances of the same data bit are extracted and combined to form a single received bit. |