Use of discrete wavelet transform method for detection and localization of tampering in a digital medical image

Use of digital images has increased tremendously in medical science and with that has increased the query on authenticity of the image. Authenticity of the digital image is very important in the area of scientific research, forensic investigations, government documents, etc. With the help of powerful and user friendly image editing software like Microsoft Paint and Photoshop it became extremely easy to tamper with a digital image for malicious objective. Of late this problem has been encountered in medical imaging also for the purpose of fake insurance claims. We propose an algorithm to address this problem by which one can detect and localize tampering in a digital medical image. This algorithm is based on hash based representation of such image and uses discrete wavelet transform method to carry out detection and localization of tampering. We will show that our algorithm is robust against harmless manipulation and sensitive enough for even a minute tampering. Our proposed technique consumes less resource as it works with smaller hash function in comparison with the similar available techniques.