Mayayana,

Seems a bit farfetched.

Not really. I created a 640x480 24 bbp image, totally light blue
(0x07F7FFF). Than I "hid" text in it in a single line of pixels. Even
though I (ofcourse) knew where I placed that text I could not see it.

I even went as far as to clear or set the lower /four/ bits of each color
byte (thats 12 bits of data per pixel ), and still had something that was
almost invisible.

Than I did the same on an image of somes face. Even though I knew where it
was, I could not find it anymore.

And mind you, that was 12 databits per pixel. With one bit per color byte
(three in total) it would be all but invisible.

Hopefully they're not being used to send nuclear codes and
only things like

They might as well.

There is a /lot/ you need to know about how the message is stored to be able
to retrieve its bits, starting with /that/ you have to look, and than
/where/. The message might start from any pixel. Also, the next data
pixel might be in any of the eight directions, and not even directly next to
the previous one. And the shorter the message, the easier it is to hide.

And thats even assuming that the message itself is not first obscured as
well ... (making it even harder to recognise patterns in the colors lower
bits).

Regards,
Rudy Wieser