On Sun, 22 Jun 1997, Steve Schear wrote:
That's the major problem with images, you need to generate your own. Unless you fancy writing an image enhancement system, and analyse the algorithms in existing systems to ensure that randomness is introduced.
There are plenty of Net-cams watching traffic or sunsets around the world. Since these images tend to change a bit from frame to frame they could cheaply and reliably provide the sorts of images which are ideal for stego. I'm not sure if you can frame-grab from such a changing Web page with the current browser features, but this should be a significant hurdle.
Or, set up your own webcam "to watch your coffee pot twice a minute" or something. Merge the crypto stream through the gifs after tweaking the brightness and contrast to avoid 0 and 255 (a light fixture with a pattern of 254/255 values gets suspicious, and is not from thermal noise - a "problem" with monochrome quickcams for night photography). Then do something like lynx -source webcam.x.y/images/coffee.gif | destegodecrypt >>reconstruct every 30 seconds (with some kind of dropout correction). [lynx is a textmode browser that works well for these types of things]. Or even an AVI for both video and sound stego.