-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 06/01/2016 03:43 AM, juan wrote:
On Sun, 29 May 2016 11:46:37 -0400 Steve Kinney <admin@pilobilus.net> wrote:
Hiding arbitrary data inside media files by flipping bits is likely to fool a human observer, but unlikely to pass through a stego detection filter without tripping an alarm.
How? Audio and video have noise. You replace the natural noise with your 'noise'. How can an observer tell if he's looking at noise inherent in audio/video signals or at encrypted, noise-like data?
Short answer: Statistical analysis; naturally occurring noise and noise introduced from a "random" source (i.e. encrypted data) and/or at random positions in the data stream are quantifiably different. Longer answer: https://en.wikipedia.org/wiki/Steganalysis Longest answer: Stenography & watermarking vs. detection of same is an ongoing arms race, with substantial advantages on the attacker's side . Example of do-it-yourself steganalysis: http://stegsecret.sourceforge.net/ :o) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQEcBAEBAgAGBQJXTxuSAAoJEECU6c5XzmuqgucH/RnqAr2Ac+QjNyR6rDN/vI3m z2wu3YgnfujgKyXqcCBY1YB8bcwHL8YBqfe6MOg4HxToSxb8wpNvKF1qS1YQ+3JG 5y7uMPVzEF4XM/cdzuspZXl06x7gdV8sJNHRsuyxxWaKzvB1zf04XaKkE9wGWm85 8fenFtQbTaQXnn1BhO+93yOjXf61W8Q+F8Fg9h/g7a6jYYjQqmCgGeED9Q4DkIfh Rui4eYRUhAC2uDa8ckvLDWUcEcHXi1eFyqEOVnmk+B0wXPXulsz8SxOvet6Igznl k4DuezjkMKbAsF4gtNmcqgQsrbeDfXmwM1/xjO8d2DKcg82jk6Veb99d35QQfzs= =DwpB -----END PGP SIGNATURE-----