DCT-Based reversible image watermarking approach

A reversible watermarking approach recovers the watermarked image to source image after extracting the embedded watermarks. This paper presents a reversible image watermarking approach that works on quantized DCT coefficients. We first introduce two parameters adjustment rules ZRE and ZRX that are used to embed and extract one bit to coefficients. We also propose CA rule to prevent confusion during embedding and extraction. Watermark embedding and extracting algorithms are then proposed by these three rules. Experimental results show that quality of watermarked image is good and the proposed approach can also detect maliciously attacked regions.