Is there a way to create an invisible watermark to place on photos.
And have it setup so when someone downloads the image or prints the page it becomes visible.
Is this possible with html, css, java, or with a third-party program?
Watermarks
I don't know about invisible watermarks, but I know you can make watermarks with the help of PHP server side language using the GD/imagemagik libraries.
Watermarks
Photoshop supports digital watermarking, though you need to register with digimarc.com first.
A quick browse of the digimarc site looks interesting - lots of interesting tools for placing watermarks, and tracking watermarked images on the web...
Watermarks
Yeah, Paintshop PRO does the same.
You can embed a digital watermark that shows up when printed. It does cost to register - probably withthe same people Digimark.
Watermarks
There are ways to kinda stop people. There is the script to prevent right clicking
<SCRIPT language="JavaScript"> var code=""; </SCRIPT> <SCRIPT language="JavaScript"><!-- function click() { if (event.button==2) { alert('This is the text in the alert'); } } document.onmousedown=click // --></SCRIPT>
OR
you can stop them from highlighting the picture by using simple HTML:
<body onselectstart="return false" ondragstart="return false">
But there are ways for people to get around it, but it will stop almost anybody that does not know how to use a keyboard. Cheers