Lossless Information Hiding in Images

6.2. Lossless Information Hiding in JPEG Images

6.2.1. Overview of Information Hiding in JPEG Images

The JPEG image format is a widely used compressed format. For JPEG images, as early as in 1997, Upham [7] first developed a famous hiding tool for JPEG images named Jpeg-Jsteg, where the secret data are embedded into the least significant bits (LSBs) of the quantized DCT coefficients whose values are not 0, 1 or −1. Westfeld [8] developed the so-called F5 algorithm, which implements matrix encoding to improve the embedding efficiency. In addition, F5 also employs permutative straddling to uniformly spread out the changes over the whole steganogram. Both these methods are irreversible with a low capacity. In the same year, Fridrich et al. [9] presented ...