A JPEG Steganalysis Algorithm with Embedded Rate Estimation Based on Multi-class SVM

The purpose of image steganalysis is to find out if the hidden messages exist in images. After differencing DCT coefficients of natural-images and stego-images, their histograms present different laws. This paper regards this as the feature vector to determine if a hiding message is in the image. Through the analysis of former feature vector, the author extracts a new feature to estimate the amount of hidden information in JPEG. The results of the experiments show this approach is effective.