In this paper, we introduce a new forensic tool that can reliably detect modifications in digital images, such as distortion due to steganography and watermarking, in images that were originally stored in the JPEG format. The JPEG compression leave unique fingerprints and serves as a fragile watermark enabling us to detect changes as small as modifying the LSB of one randomly chosen pixel. The detection of changes is based on investigating the compatibility of 8x8 blocks of pixels with JPEG compression with a given quantization matrix. The proposed steganalytic method is applicable to virtually all steganongraphic and watermarking algorithms with the exception of those that embed message bits into the quantized JPEG DCT coefficients. The method can also be used to estimate the size of the secret message and identify the pixels that carry message bits. As a consequence of our steganalysis, we strongly recommend avoiding using images that have been originally stored in the JPEG format as cover-images for spatial-domain steganography.
[1]
Sushil Jajodia,et al.
Exploring steganography: Seeing the unseen
,
1998,
Computer.
[2]
Jiri Fridrich,et al.
Secure Steganographic Methods for Palette Images
,
1999,
Information Hiding.
[3]
Sushil Jajodia,et al.
Exploring steganography: Seeing the unseen
,
1998
.
[4]
Sushil Jajodia,et al.
Steganalysis of Images Created Using Current Steganography Software
,
1998,
Information Hiding.
[5]
Ross J. Anderson,et al.
On the limits of steganography
,
1998,
IEEE J. Sel. Areas Commun..
[6]
Andreas Pfitzmann,et al.
Attacks on Steganographic Systems
,
1999,
Information Hiding.