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Wouldn't a simple re-encode break any sort of stenography?


No. There are algorithms out there that can survive compression[1] by encoding statistically over an image instead of just bit manipulation.

You can also embed data in the audio channel by alternating between two imperceptible echo kernels for 1/0[2]. This is extremely compression resistant.

1: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumb...

2: http://www.slidefinder.net/a/audio_steganography_echo_data_h...


Surely it would be possible to create encoding resistant stenography. Will the stenography be affected, sure, but it should be possible to create error-resistant stenography up to a certain point.


Stenography: encode information such that it is below the human detection threshold.

Lossy compression: discard all sub-threshold information.

Thus, in the general case it's fundamentally impossible. You can make a scheme that will survive certain known encoders and bitrates, but you can't make one that will survive all lossy compression.




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