Yup, for then it would be a new work in its own right.

Bear in mind that it is only the NEW image over which you would have copyright. It would not extend to the original, public domain work.

That is my understanding, but I am not an expert so do not take me at my word.

Instead, it may prove beneficial to have a read up on this and other issues at one of the many great copyright and intellectual property resources out there. Here's a good one:

[fairuse.stanford.edu...]

Syzygy

Jim