Copy move tampering some new approaches of the detection and localization in a digital image

Abstract

quotImages speak. They tell us stories. Digital images carry plethora of information. The availability of cost-effective digital camera-enabled devices has made capturing images a child s play. Statistics witnesses that the use of social networking sites has influenced people s appetite for digital images. Billions and billions of photos are uploaded, shared and forwarded on these platforms. This makes every user an active source of the digital information. newlineThe availability of easy-to-use image editing software helps novice and experts as well capable of creating realistic alterations in these digital images. These alterations could be harmless changes for fun or serious image tampering with malicious intentions. This fact raises eyebrows and questions the authenticity of a digital image. When these digital images are used for specific purposes like news broadcasts, research publications, sports, entertainment, fashion, advertisements, legal proceedings etc., this problem becomes more critical and challenging. Therefore, digital image tampering has since long attracted the research community of image processing. newlineAmong various tampering operations, copy-move tampering is one of the easiest approaches and therefore the most common approach. In the copy-move tampering process, copying and pasting are done on the same image. Hence colour, noise component, intensity range and other properties of the image remain almost unchanged. It makes tampering detection difficult when no clue about the tampering is available other than the image itself. Further, to camouflage tampering some tricks to hide the footprint of tampering are used, such as blurring of the edges of the copy-pasted pat of the image. Technically this can be achieved by some image processing methods, e.g., JPEG compression, addition of Gaussian noise, brightness change, colour reduction, contrast adjustment etc. Occasionally some geometrical transformations such as scaling and rotation of the copied regions before pasting them somewhere else in the same...