OVERLAPPED WATERMARKING FOR SECURED DATA TRANSMISSION..

A high efficiency multi-layer halftoning based watermarking which adopts noise-balanced error diffusion to achieve high embedding capacity and improve security aspect. The encoder employs an Efficient Direct Binary Search (EDBS) and Look-Up-Table (LUT) method to embed multiple watermarks. The decoder simply utilizes the Least-Mean-Square (LMS) and naive Bayes classi?er to extract the embedded watermarks in multi-layer framework with self-decoding capability. The proposed watermarking preprocesses the watermark to reduce its bit depth. The 8-bit grayscale image (with 256 levels) is converted into a new image representation (with a lower bit depth) using the uniform scalar quantization with ?xed divisor. The distance metric can be considered in determining the quantization. Experimental results suggest that only minimum milliseconds are required for embedding multiple watermarks. - See more at: