I have taped some videos using DVBDream with a DVB-T Tuner card.
The oldest ones have a different watermark, which I want to erase and/or replace.
Screenshots are linked to, just to avoid large images here.
Here is one screenshot (older watermark):
http://img252.imagevenue.com/aAfkjfp01fo1i-24965/loc235/66358_ITV4Tour_00001_122_235lo.jpg

and with the newer watermark (which I intend to use to replace the older one with):
http://img200.imagevenue.com/aAfkjfp01fo1i-11105/loc447/66359_ITV4Polic_00024_122_447lo.jpg

I wish to retroactively add the newer watermark to copies of the videos (all of which have FILENAME_COPY.mpg in their titles) so they look newer, is this possible with such software?

Images are only used here for fair use purposes. The videos themselves are saved for timeshifting purposes, so no copyright is broken.

Please can someone recommend a good, and spyware-free watermark eraser/replacer?
(some free utilities have spyware in, and this does not mention piracy, in accordance with site rules)

Thanks

I don't sure that you can find free software for remove/replace watermark. But if you interesting can recommend VideoCharge Studio - no free, but has free trial.