METHOD AND APPARATUS OF ADAPTIVE QUANTIZATION WATERMARKING WITH 2 OR MORE STEP SIZE FOR IMAGE

摘要

A method and an apparatus for adaptive quantization watermarking are provided to insert watermark information into an image adaptively, thereby doubling a non-visual effect of watermark. An edge component value of an image, into which watermarks are to be inserted, is calculated(S111). The image is divided into two or more sections, to which different quantization step sizes are applied according to an edge component value, based on a predetermined reference value(S131). Corresponding quantization coefficients are applied to the sections, thereby inserting watermarks into the sections of the image(S132).