Quantization effects on digital watermarks

摘要: Abstract Digital watermarking is the process of introducing small modifications into a copy digital document that can be detected later. The embedded information used to determine document's owner or simply distinguish several copies. However, coincidental malicious “attacks” degrade robustness watermark detection. Here, uniform scalar quantization watermarked documents investigated theoretically, extending results from theory dithered quantization, and experimentally. by an independent additive pseudo-noise sequence. statistical distribution errors depending on statistics host signal detection via correlation. Experiments with JPEG compression image DCT-domain demonstrate usefulness presented theory.