The invention concerns a method of processing a set of coefficients representing
a digital image (300) with a view to an insertion of at least one item of
watermarking information in said image, this image being liable to undergo a set
of geometric transformations and said coefficients being grouped together in regions,
said method being characterized in that it includes a step (E220) of determining,
amongst at least some of said regions, a set of so-called acceptable regions, adapted
to receive said at least one item of watermarking information; and a step (E230)
of sequencing, according to at least one predetermined criterion, at least one
part of said set of acceptable regions, in an order which is invariant with respect
to at least one of said geometric transformations.