International Journal of Engineering and Technology

Information security plays a very important role in fast growing information and communication technology. Few applications like medical image security and satellite image security needs to secure only selected portion of the image. This paper describes a concept of selective image encryption in two ways. First method divides the image in to sub blocks, then selected blocks are applied to encryption process. Second method automatically detects the positions of objects, and then selected objects are applied to encryption process. Morphological techniques are used to detect the positions of the objects in given images. These two approaches are specifically developed to encrypt the portion of an image in medical images and satellite image.