I looked at the page on Grain alaising. I decided to do a patent search at
using "Applied Science Fiction" as the
Assignee. This found 7 patents, but none related to grain or noise. After
looking at a couple of the patents, I decided to search on the common
inventor, "Edgar; Albert". Bingo! See US5673336:Automatic cross color
elimination.
The abstract read:
Color crosstalk is determined between layers of an image storage medium
based on the cross correlations and autocorrelations of noise in the grain
pattern in each layer of the image storage medium. Rather than relying on
prior measurement under laboratory conditions, the invention scans the
storage medium in a plurality of spectral bands to derive the record stored
in each of the dye layers. A computer derives the autocorrelations and the
crosscorrelations of a group of pixels between the plurality of color
records of the scanned images each of which corresponds to one of the
spectral bands. The invention is based on the observation that as each dye
layer is deposited separately in the film, one would expect that the "noise"
from the grain boundaries in one layer to be independent from the "noise"
due to the grain boundaries in other layers. If there is correlation in
noise between separate color scans, it is because the scanner is measuring
the grain boundaries in more than one layer in the color scans.
--------
Dean Shough
dean.shough@lmco.com
