A Robust Digital Watermarking Algorithm Based on Integer Wavelet Matrix Norm Quantization and Template Matching

As a protection and authentication technology, digital watermarking technology has been used in digital image field. A robust digital watermarking algorithm is proposed based on integer wavelet transform to estimate integrity and authenticity of digital images. Using matrix norm quantization, it embeds watermarks into medium-frequency and high-frequency detail sub-bands of digital images’ integer wavelet domain. The scheme realizes blind watermark extraction without any extra information. By shaping the watermarked image before extraction, the precision of the extracted watermark is enhanced. Attacking experiments show that the algorithm not only has both robustness and sensitivity, but also exactly locates distorted area, so it is an effective robust digital watermarking algorithm for digital image field.