Texture feature based oblivious watermarking with slant transform using fuzzy logic

An improved method of robust gray scale water marking is proposed in this paper. The proposed method employs slant transform using Quantization Index Modulation (QIM).The threshold used in QIM of each 8x8 block is computed using fuzzy logic, based on texture parameters namely variance, uniformity and entropy. The experimental results confirm that the proposed method is highly transparent and the watermark is recovered from seriously distorted images with attacks such as Gaussian Noise (GN), Salt and Pepper noise, vertical flipping, low quality JPEG compression and cropping the image to 25 %.