Adaptive watermarking technique based on human visual system and fuzzy inference system

A robust image watermarking scheme based on human visual system is proposed. The perceptual quality of the watermarked image is controlled by determining adaptive scaling factor for each individual pixel value. To determine the adaptive scaling factor, human visual system (texture masking) and fuzzy inference systems were used. The quality of the proposed scheme is tested against various attacks (Histogram equalization, rotation, Gaussian noise, scaling, cropping, JPEG compression, Y-shearing, X-shearing, median filtering, affine transformation, translation, sharpening, blurring, average filtering). The perceptual quality of watermarked image is calculated using peak-signal-to-noise-ratio, whereas the extracted watermark´s quality is measured using normalized correlation.