I. Introduction
Image steganography is a technique that is commonly known as covert communication. It hides a secret message in a seemingly harmless image. As an opponent, image steganalysis is a reverse analysis technique that detects steganography. Its purpose is to determine whether the image is embedded by some steganographic algorithms. Generally, steganalysis relies mainly on features and classifiers, so the choice of steganalysis features and classifiers is a core issue.