Since you are hosting your images on Photobucket, I presume you'll need the images watermarked prior to uploading them instead of being dynamically watermarked every time your visitors sees them, so I have created this demo script which does a batch, permanent watermarking to each image file found in a specified folder and stores the watermarked version in another.
And on the link to watermark the images below, you may find that there are values which looks editable within the URL. They are. If you know what RGB is, please go ahead and edit the respective values and see the results for yourself. Accepted values are integers between 0 - 255. And the last parameter changes the transparency of the watermark. Edit it to achieve the ideal translucent effect that you desire. Valid values for it are integers as well, but just 0 - 127. But if you are lazy, just click on the link. I have set 255, 255, 255, 32 as the default anyway.
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