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A comment on Why does Numbers hide a huge PNG file in exported Excel sheets?. Parent comment

Re:Why does Numbers hide a huge PNG file in exported Excel s... by DanBC on Monday August 18, 2014 @10:03AM (#8192629)
Most steganography is trivially easy to detect. Good steganography needs a lot of cover data and better systems than manipulating the LSB.
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Re:Why does Numbers hide a huge PNG file in exported Excel s... by nitrogen on Monday August 18, 2014 @10:17AM (#8192690)
If the distribution of bits in an encrypted stream is indistinguishable from normal image dithering, wouldn't encrypted steganography be hard to detect?

It wouldn't survive any lossy image transformations, though.

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Re:Why does Numbers hide a huge PNG file in exported Excel s... by MichaelGG on Monday August 18, 2014 @10:22AM (#8192713)
Steganography on normal pictures. If the picture is just random pixels then it would not be detectable.
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Re:Why does Numbers hide a huge PNG file in exported Excel s... by DanBC on Tuesday August 19, 2014 @01:46PM (#8198717)
Randomness is something that cryptographers have spent a lot of time studying.

Introducing non-random data into a random data stream is easy to find unless you're very careful about the amounts of data-to-be-hidden and cover-data.

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Re:Why does Numbers hide a huge PNG file in exported Excel s... by MichaelGG on Tuesday August 19, 2014 @06:07PM (#8200084)
If you encrypt the data first, then you're inserting "random" data as far as analysis goes.
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Re:Why does Numbers hide a huge PNG file in exported Excel s... by hamed_benz on Wednesday August 20, 2014 @03:58AM (#8201453)
salam
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