If so, how?
Does it require any other Adobe software for this feature to function properly (e.g. Photoshop), or can Bridge be used standalone for this purpose?
(This is an important distinction for my use in making recommendations, as Bridge is completely free.)
No.
Adobe Bridge is not capable of manipulating or editing images, in that sense. Bridge is primarily meant for browsing and managing files.
In order to edit images, you will need a raster-based editing program such as Photoshop or Gimp.
While Bridge does allow you to watermark images in bulk, it is my understanding that it does so using Photoshop actions.
Actually, the answer is yes. Adobe Bridge has just enough functionality and can, with the use of some javascript, add watermarks to images. I have coded a script that watermarks images for me but it's specific to what I personally need. I'm currently working on making it more user-friendly and adding in various settings to allow customization.
The drawback is that it will be slower than if you did this through Photoshop or another graphics editing program. The reason I needed Bridge to do this was because I have a sequence of processing for images when I do photos for a client. Extract jpg from CR2, copy jpgs to that users specific local folder, watermark them with a "PROOF" logo, upload them to their album on my website and, once they submit an order, get the order and label all the photos the client wants. This is all done in Bridge via javascript with only a few clicks on my part to set up for the specific client.
An option I used to use was to have Bridge create a .bat file then run it. The .bat file would run ImageMagick on the images and add the watermark. So that's another option, though it isn't specifically Bridge doing the watermarking. There is also a way to have Bridge "talk" to Photoshop and tell Photoshop to do certain tasks which could include watermarking images in batch.
For anyone interested, I have a first draft of a JavaScript for Bridge that will watermark jpg files with a stamp from a png file. The png file can have an alpha channel (transparent background). I'm trying to make it as simple as possible to use. If you have any comments or suggestions, please let me know. As of right now I only have 2 blend modes available for the watermark stamp: Normal and Softlight. Those are the 2 I use the most so I started with those. The script also contains functions for Darken and LinearLight blend modes but I haven't fully tested those yet so they aren't used. You can easily add those into the script by following the pattern.
Go to the link below and save the file to your computer. Save it as "Watermark.jsx". Then copy the file to your Bridge Startup Scripts folder. Then restart Bridge. If you did that correctly, you should see a new menu item under the Tools menu named "Watermark JPGs". Just click on that to open the dialog. It should be pretty simple to figure out. I hope.
