[WM]: reaction of watermark to different compression degrees in one video frame

[Enrico Hauer <enrico.hauer@ipsi.fraunhofer.de>]

Hi Watermarkers,

during analysis of MPEG videos I have seen differences of the quantization degrees. Sometimes the quantization step fluctuates
between
2 and 16 in one frame and it had different effects to the watermark quality. Sometimes it is to visible sometime to fragile.

Do you know techniques and/or papers how a good video watermark should react to these different degrees. Different tests have shown
that i need a variable watermark strength dependent on the quantization degree but this is not secure.

Regards,
Enrico

--
Enrico Hauer, Dipl.-Inf. (FH)
Research Associate MERIT
Media Security in IT
Fraunhofer IPSI
Dolivostr. 15, 64293 Darmstadt, Germany
Phone:  +49-6151-869-4880, Fax:  +49-6151-869-6847 enrico.hauer@ipsi.fraunhofer.de http://www.ipsi.fraunhofer.de/~hauer
http://www.ipsi.fraunhofer.de/merit


______________________________________________________________________________

Watermarking Mailing List - http://www.watermarkingworld.org/ml.html
To unsubscribe send email to "majordomo@watermarkingworld.org" with
"unsubscribe watermarking YOURMAIL" in the body.
______________________________________________________________________________