Detection of Contrast Enhancement Forgery in Previously and Post Compressed JPEG Images

Nowadays the digital images become a very powerful source of communication. Digital images are consider to be proof in many investigation. So it is very important to provide security to these images, But with the advancement in the technology many photo editing tools like adobe photoshop etc. are used to enhance the features of original image which makes forged image. Thus it is important to detect this type of image forgery. Retouching is one of the forgery type in which contrast of images are enhanced or reduced. Our proposed system is about Contrast Enhancement Detection. The Contrast Enhancement Detection is done by Numerical Measures of image Estimation using Zigzag Zonal DCT Band. This algorithm are applicable for Previously and Post Compressed JPEG Images. According to these features SVM classifier gives detection result. Our proposed technique gives better accuracy and also detects contrast enhancement in all types of images.