Electromagnetic field (EMF), Electromagnetic radiation (EMR), Electromagnetic pollution.
Tamper localization capable image watermarking scheme is able to detect the location of manipulated areas, and validate other areas as authentic. The usage of block average intensity in the tamper localization process is one of the popular techniques due to its easy implementation. The effectiveness of using existing and proposed average intensity techniques for tamper localization is tested. The results show that the existing tamper localization process will fail in certain conditions and cause some tampering to be left undetected. However the proposed tamper localization algorithm successfully identifies the region that has been manipulated when the image is received. The accuracy of 8 pixels is achieved by proposed algorithm.