An image watermarking approach based on Set Partitioning in Hierarchical Trees(SPIHT)algorithm

In recent times, digital watermarking has become one of the advanced technologies to protect images from illicit manipulations. A non-blind robust Discrete Wavelet Transform domain watermarking approach for images is introduced in this paper. Based on the parent-child relationship between wavelet coefficients, the Set Partitioning in Hierarchical Trees (SPIHT) algorithm is applied on the transformed host image to find out the significant coefficients for embedding binary patterned watermark image. Higher level of security is achieved by scrambling the watermark using Arnold transform. The selected significant wavelet coefficients are adapted using Noise Visibility Function (NVF) to achieve enhanced imperceptibility. The scheme is tested against various image processing operations including JPEG compression, noise addition, filtering, cropping, histogram equalization and contrast adjustment. The experimental results showed that the proposed algorithm is highly robust.