Alpha Channel base Data Hiding using Compressive Sensing
Ripal Patel, Jay Amin · International journal of advance research and innovative ideas in education · 2016
In recent day image ownership authentication has drawn a sharp attention due to easy availability of the internet and inexpensive digital recording and storage peripherals has created an environment where duplication, unauthorized use, and distribution of the digital content has become easier that leads cybercrime. Due to the wide distribution and usage of digital media, an important issue is protection of the digital content.There is a number of algorithms and techniques developed for the digital watermarking. Today already proposed different color image watermarking frameworks for embedding a color watermark within a color input image. An input image is divided into some blocks. In proposed technique use embed watermark at two LSBs in alpha channel of all such blocks. Although alpha channel is used for controlling the transparency of the image, but two LSB's in the alpha channel are unused bits. In this technique we have used these two bits for embedding information. They don’t have any contribution in luminance and chrominance factor. For that reason watermark is fully invisible to the Human Visual System (HVS) and no bits are changed in the RGB channel of the input image and for that reason no color information of the input image have been lost. So the color density of the original and watermarked image is same. Use the compressive sensing (CS) method that provides reconstruction of the signal/image. CS can provide good quality of image reconstruction with smaller number of samples and at the same time to detect and extract the watermark. At the extraction end quality of input image and watermark is same as it is.