A robust means of watermarking a digitized image with a highly random
sequence of pixel brightness multipliers is presented. The random
sequence is formed from `robust-watermarking-parameters` selected and
known only by the marker and/or the marking entity. A watermarking plane
is generated which has an element array with one-to-one element
correspondence to the pixels of the digitized image being marked. Each
element of the watermarking plane is assigned a random value dependent
upon a robust random sequence and a specified brightness modulation
strength. The so generated watermarking plane is imparted onto the
digitized image by multiplying the brightness value or values of each
pixel by its corresponding element value in the watermarking plane. The
resulting modified brightness values impart the random and relatively
invisible watermark onto the digitized image. Brightness alteration is
the essence of watermark imparting. Detection of an imparted watermark
requires knowing the watermarking plane with which the watermark was
imparted. Regeneration of the watermarking plane requires knowledge of
the robust-marking-parameters used in its formulation. This is generally
only known to the marker and/or marking entity. Once regenerated the
watermarking plane is used together with a verifying image located in a
`visualizer` to demonstrate the existence of the watermark.