Improved Edge Based Steganography Scheme for GrayScale Images in Spatial Domain

The steganography algorithms are most popular in spatial domain. however in most existing algorithms the information used to embed in any region in spatial domain without considering any relationships of the image content. There for some structural asymmetry exists in those images which have smooth regions like sky, even when the size of information is small. There for this leads poor visual quality and low security based on some analysis and extensive experiments. The improved edge based steganography scheme embeds the secret information in the edge regions of the images without disturbing the smooth region. Generally the regions located at the shaper edges present more complicated statistical features and are highly dependent on image contents. So it is more difficult to observe changes at sharper edges than those in smooth regions. When embedding rate increases remaining edge regions can be released for information hiding by changing some parameters. so that it will achieve more embedding capacity also enhances the security as compared to existing approaches such as typical least significant bit based approaches and PVD based methods. The new scheme also improves the visual quality of stego images.