WATERMARKING ALGORITHM USINGEDGE DETECTION TECHNIQUE AND DCT,DST, FFT

[摘要] This paper proposes robust hybrid watermarking scheme for grey scale images using block processing method. The proposed watermarking technique developed using combination of various transforms such as Discrete Cosine Transform (DCT), Singular Value Decomposition (SVD), Discrete Sine Transform (DST),Fast Fourier Transform(FFT) and edge detection technique. Pixel values of the blocks are modified based on the threshold value determined from edge detection. Later on from the modified block, the singular values using SVD are chosen. Using singular values watermark is embedded. Reverse process is used to extract watermark image from the watermarked image Evaluation metrics used to analyze the experimental results are Correlation (CORR) &Peak Signal to Noise Ratio (PSNR).Proposed work will be suitable to applications such as copyright protection and Copy control.

[关键词] Watermarking Algorithm;DCT;SVD;DST;FFT;watermark;copy right protection;CORR and PSNR.