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hi peeps
I already know that we can encrypt a message on a pic such that other people can only view the image but not the message. And for reading the message a decypting technique is used.
Now the question is, how can we do this encrpytion/decyption on a photograph???
It's data after all?If you're encrypting something at the bit level I dont think it'll matter whether it's a txt or a jpg file
google abt ur querry yaar..
google for steganography, what your talking about sounds more like the program "camoflage"(sp??) than any real kind of encryption.
Here is a link to find info abt Steganography.. they have a complete section on it.
www.astalavista.com
Yes, let's clarify what your talking about. You want to make it so an image is not viewable? Do you want to hide the fact that the image is protected? What I mean is, if someone intercepts the message in transit, are they going to recognize from casual observation that there is a hidden image in the message or it's attachments?
For the sake of this discussion, I'll ridiculously simplify these terms.
Encryption is essentially locking, so those who are not authorized, can not view the data.
(Those of you studying for Security+ or CISSP, this is Confidentiality, from the C.I.A. Not CIA as in spooks, CIA as in the goals of information security.)
If you want to hide the image so people don't know it's there, then you could use something like...steganography, to hide the data for the image inside another set of data. This is Obfuscating. For those of you in the audience not familiar with that term, it means 'to obscure'.
M-W.com: obscure
Pronunciation: äb-'skyur, &b-
Function: adjective
Etymology: Middle English, from Middle French obscur, from Latin obscurus
1 a : DARK, DIM
b : shrouded in or hidden by darkness
c : not clearly seen or easily distinguished : FAINT
2 : not readily understood or clearly expressed; also : MYSTERIOUS
3 : relatively unknown: as
a : REMOTE, SECLUDED
b : not prominent or famous <an obscure poet>
So, which is it? Do you want it to be confidential, or obscure?
</end of ridiculous simplification and misappropriation of these terms>
Hi codenamevirus and welcome to AO.
Your question is not entirely clear, but I believe that therenegade has answered it........."they are all data"?
As I currently understand you, you are saying that we can hide a text file within an image file (.jpg, .bmp, .gif etc.) So can we hide an image file inside a text file?
Well, if that is your question, then the answer is "yes" in theory :D
As correctly mentioned by the above posters, this is "steganography"
This leads us to the practical considerations of scale ..............you can hide a small thing within a large thing, but you cannot hide a large thing within a small one.
Document files are generally very small and picture files are much bigger. In the reverse situation it would not work :)
You would need a large document and a very small/compressed picture. I would suggest that a picture in a music (audio) file would be a better option. And I have no idea what a video file would be like. Both obey the large to small rule.
You have raised an interesting question, I shall have to go and experiment.
:)
A very simple way to use steganography.
Open an image in a photo editing suite add a new layer, insert into that layer some text, making sure the text is the same colour as the back ground. To decrypt seperate layers.
hi
thanks for all ur replies.
i'll make my question more clear now...
Basically what I wanted to do was, encrypt the message(the text) on the photograph(most probably, .jpeg or .gif), and when I send it to someone(say A), only he's capable to decrypt it and view the text I hav sent. But, for everyone else its just an image(they aren't able even to think that the image can also hav a secret message!!). So, do u got my point now?? i.e. only the two people(myself and the perosn A) know that the image has a message and can read the message by using the decryptin techniques, and for eveyone else its just an ordinary image!!! Remember, I want to hide my text and not my image, anyone can download and see that but only myself and A can read the text encrypted in it!!! After all the replies, I think what i want is obsuring (i aint sure, yet!)
OK,
That is normal steganography. Do a google search for "freeware" then look through the various sites for data encryption, data proyection and you should find a free product.
Remember that your friend will need a copy as well.
:)
i have done it with pgp, I believe almost any encryption software(that does data) can do this.
PGP does enctryption not steganography, the two are not the same thing!
Search sourceforge for a program called steghide, works very well and is windows/linux based.
I have been using stego for several years now, In fact its one of the ways I like to pass around passwords to friends, or "special" webistes that are only accessable for a few hours.
steghide will even give you info on the hidden file with the correct passphrase.
And also tell you how much you can store inside and image OR wav file.
When doing stego there are two files. The cover file (image or wav) and the content file (Text, image, wav, mp3, exe, zip, rar, unrar...any file type)
One thing I like to do is take an mp3 convert it to wav. That gives me a nice large file to use. Then I embed (encrypt) my txt file or in some cases a bmp,jpg with text into the wav file.
Once I simply read a book into my computer and used the 20mb file to store a zip file in.
There's some more advanced ways that involve using lossless compression methods and hiding/compressing the file..
txt -> bmp -C> png
and ways to retrieve that.
In terms of hiding the stuff you could write your own app to do it and to recover it. It's best if you encrypt whatever you want to hide first, there are programs out there that can sniff out steganography sometimes and if there's no added layer of protection you'll get 'pwned' quickly :)