From the many questions I receive it's clear that protecting ones assets is a subject of interest and worry for many.
The following table Summarizes the different protection methods sorted by their effectiveness.
|Post only unimportant images||Not much||Not much either||Why bother to have a Web presence if not to display your best?|
|Post reduced Size low quality images||Better than above||Worse than above||Might leave wrong impression on your browsers|
|Visual watermark, as copyright text visible on the image.||States ownership of images||Time consuming, can be removed||Reducing image quality for the viewers, distracting|
|No right mouse button||None||Doesn't work on non PC||Waist of time, Mac users won't even know it's there|
|Transparent image on top of actual one||Better than above||None||Better than all above, doesn't stop capturing your images.|
|Embeding the images into a Flash, Shockwave, Quicktime presentation||Image quality maintained||No protection at all||Time consuming, offers no protection|
|Digital watermark||Hidden, not many know it's there||Not many know it's there||Verification on the web needs a web spider service, to trace the images. Gives the most in proving ownership|
Digimarc ImageBridge plugin for Adobe Photoshop, is a subscription based service available from Digimarc. After registration with Digimarc (up to 99 images for free) one gets a PIN and ID numbers. Using this info the plugin embeds a digital code into the image. This code is applied as a noise or grain pattern to the image. Since the code can withstand alterations to the image and still be readable. The strength of the noise - code is set in the plugin, less visible = less durable, more visible = more durable!
Since Digimarc is available for the major imaging software any one can verify the existence of a Digimarc watermark in an acquired or downloaded image.
Once the photos are on the Web and one wants to trace if and where the images were copied to, Digimarc offers a Digimarc MarcSpider an image tracking which is also subscription based. MarcSpider will spider the Web returning reports which contain details on when and where the protected images are found.