If I wanted to remove a Water Mark from an video on my mobile phone what

[sniffysam]

software would I need to downlaod.? In addition to this if I wanted to replace the Water Mark with one of my own is there Software on the net that can do both Remove/replace?
And of course is there any 'Open Source' software that is capable of this?

[Frog Five]

You're asking the impossible, there. You can't just add and remove these things. Watermarks are added to copies of the original and are permanent. All you could do in an editor is put an opaque graphic over the watermark.