关键词: 水印 时域均匀区 四叉树

Abstract:

A spatial watermarking algorithm is proposed in this paper. The amount of watermarks to be embedded varies with the size of each sub-image adaptively  partitioned from an image. A quadtree structure of the image is used as a key to extracting the watermark, which indicates the size and position of each  sub-image. Three segments in the sub-image sequence representing large, medium and small blocks are chosen to be the watermark containers, so as to ens ure the water- marking to be robust. From experiments, results indicate the watermarking algorithm is effective in resisting the JPEG compression with a ny ratio, rotation with anv angle, filtering, noising, cutting and scratching.

Key words: （watermarking, spatial even block, quadtree）