These ideas use digital cameras that would automatically embed images or sound into digital photos, which typically contain large amounts of redundant data.
PART I - EMBEDDING SOUND IN PICTURES
It'd be nice to be able to embed a short sound bite in digital photos to enhance the
experience. E.g. "Happy Birthday", or "Oh baby, oh baby, you're much better than my husband"
Some newer digital cameras can record sound and other movies. However, the formats tend to be (1) JPG - picture only (2) MP3 - sound only (3) MPG - movie.
The only sound and picture format above is the MPG, but that takes up a whole lot of room on the flash disk.
New formats are unwelcome, because none of your friends will likely have devices that can play the picture.
My idea uses a digital camera with a mike. You could embed a short sound bite in the least-significant bits of the image. It would still be viewable on any conventional viewer, and the recipient could play the sound using the right freeware app, another camera, or a special viewer.
Enhanced experience; no increase in file size; undetectable loss in quality; backwards/ universal compatibility
PART II - EMBEDDING PICTURES IN PICTURES
Ever take pictures you shouldn't have, but really want to keep? Nickerless Betty in accounts? Stag night photos?
You could hide the flash disk. Some cameras let you hide tagged photos. But eventually, someone might find them. Maybe you want to send the photos to your buddies, but don't want their employers' entire IT department to view your latest conquest.
The digital camera could encode over existing photos in memory. These boring, generic holiday snaps would conceal the real image encoded into their least-significant bits.
Nobody, not even another user of the same camera would be able to tell that the images displayed were not the true images. Only by pre-entering a unique code can the hidden pictures be seen. Like the above idea, this uses existing file formats and freeware software viewers.
Steganography is a thoroughly baked (but little known) technology (see link). The problem is that the users are mostly criminals and cyber geeks. Nobody else can be bothered with the hassle. These applications make its use automatic and uncomplicated.