The Integrity Of The Digital Image Content Authentication And Tamper Localization

Digital images nowadays have been widely used in everyday life．However, A bigchallenge, the security of information is offered by image processing techniques.．So checkingwhether the image is tampered maliciously or not and how to ensure the integrity androbustness of images is becoming more and more important．The hash based on imageauthentication technology exactly satisfies with this need．Further，the hash, based on imageauthentications scheme apply a perceptual hash function (PHF) to extract a set of featuresfrom the image which can reflect the content of the image to form a compact representationthat can be used to authentication．Compared with the digital watermarking techniques，thereis no distortion introduced in the original image，moreover the image hash is an entityseparately．By reason that the randomness and unpredictability, any key information will notbe leak by perceivable image hashing algorithm.Through the research of image feature extraction schemes proposed a Radon transformand geometric moment invariants based image regularization process, eliminate the effects ofrotation on the image so that more robust image hashing, hash algorithm has been studied inrecent years, a new image, and post-implementation evaluation. And made a chunk oftwo-dimensional discrete cosine transform-based authentication method, by extracting blockfeature, and select the appropriate threshold for quantitative, so ensure the robustness of theauthentication methods at the same time, increases the sensitivity of authentication for imagetampering, while positioning can be tampered with.