摘要 |
A system, method, and product provide distortion compensation when watermarking a host signal with a watemark signal. The watermark signal includes watermark-signal components having watermark-signal values, and the host signal includes host-signal components having host-signal values. A system includes an ensemble designator that designates a plurality of embedding generators, each corresponding to a single watermark-signal value of a co-processed group of one or more watermark-signal components. Also included is an embedding value generator that generates embedding values by each embedding generator. The system also has a point coder that sets at least one host-signal value of one or more selected host-signal components to a first embedding value to form a composite-signal value. A distortion compensator modifies at least one composite signal value. The distortion compensator includes a difference signal generator that generates a difference signal component having a first difference-signal value that is the difference between a host-signal value and its corresponding composite-signal value. The distortion compensator also includes a difference signal processor that scales the difference-signal value by a scaling factor, A distortion compensation combiner then generates a distortion-compensated composite signal based on the scaled difference-signal value and the composite-signal value. The distortion compensator may modify the composite signal value based on the number of possible watermark signal values to be embedded, a watermark-induced distortion level, an expected channel-induced distortion level, and a reliability of extracting the watermark signal.
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