Looking for high capacity, invisible (for human eye) watermarking algorithms, can be easly detectible

Hi, I am looking for image watermarking algorithm with specified features:

#1 High capacity (as much as possible, for example jpg in other jpg)

#2 High robustness ( *print, make foto -> watermark should still be detectible* )

#3 Algorithm should only work on image not on file headers etc...

#4 It can be easly detectible for steganalisys (it is really not important) but watermark should be invisible for human eye.

Does anyone know an algorithm that meets these or similar requirements ? Where should I search more info ?

Answer 1

[Image Analyst]

I think there are many algorithms that can do that. It sounds like standard steganography, and many methods are available that produce invisible watermarks but are still detectable by algorithms despite attacks of scaling (spatial and intensity), cropping, rotation, annotation, etc. Go here to read up on some of them:

http://www.visionbib.com/bibliography/contentschar.html#OCR,%20Document%20Analysis%20and%20Character%20Recognition%20Systems