I would like to say :
vyycd gow mcgr uuey
Apologies first: I do not know French. This is not a solution, just a possible approach.
What we know:
My approach would be:
1. cut the bits according to the dark borders
2. try to rearrange it so that the rectangular shape of the letters are kept.
3. Preferably the dark bits will form a symbol/ pattern when assembled.
4. read from left to right, then from top to bottom.
I am at my wits' end, and hope this may help anyone trying to solve this...